In order to allow only 2 decimal places in the textbox use the regular expression validator. In the validator control there will be a property called ValidationExpression,use this property to assign the valid expression as shown below.

<asp:TextBox ID=”_tbCost” runat=”server” TabIndex=”4″></asp:TextBox>

<asp:RegularExpressionValidator ID=”_ReqExpressionPhoneNo” runat=”server” ErrorMessage=”Enter numbers & ‘.’ only,should contain only 2 decimal places.” ControlToValidate=”_tbCost” Display=”none” ValidationExpression=”(?!^0*$)(?!^0*\.0*$)^\d{1,18}(\.\d{1,2})?$”>

</asp:RegularExpressionValidator>

This is the expression that allows only 2 decimal places

ValidationExpression=”(?!^0*$)(?!^0*\.0*$)^\d{1,18}(\.\d{1,2})?$”

And also for more information on regular expressions see the below link:

Also look at: http://regexlib.com/Search.aspx?k=decimal&c=-1&m=-1&ps=20

Happy Coding……………

SalesReport.Ascx

<%@ Control Language=”C#” AutoEventWireup=”true” Codebehind=”SalesReport.ascx.cs”
Inherits=”Epod.UserControls.SalesReport” %>
<div id=”divgridView” class=”grid”>
<asp:GridView ID=”gvProducts” runat=”server” AllowSorting=”false” AllowPaging=”false” AutoGenerateColumns=”False”
CellPadding=”4″ GridLines=”None” ShowFooter=”false” OnRowCommand=”gvProducts_RowCommand”
Width=”100%”>
<Columns>
<asp:TemplateField ItemStyle-HorizontalAlign=”Left”>
<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID=”_btnExpandandCollapse” runat=”server” Text=”<img src=’../images/expand.gif’ alt=’Expand to see detailed report’ border=’0′ />”
CssClass=”GridViewDataHyperLink” CommandArgument=’<%# Container.DataItemIndex %>’
CommandName=’<%# Eval(“ProductId_pk”) %>’ ToolTip=”Expand to see the detailed report”></asp:LinkButton>&nbsp;&nbsp;
<asp:Label ID=”_lblEmployeeName” Font-Bold=”true” runat=”server” Text=’<%# Eval(“ProductName”) %>’></asp:Label>

</td>
</tr>
<tr>
<td colspan=”2″>
<asp:GridView ID=”gvProductOptions” runat=”server” CssClass=”GridView” AllowSorting=”True”
Visible=”false” AutoGenerateColumns=”False” CellPadding=”4″ GridLines=”None”
ShowFooter=”True” AllowPaging=”true” PageSize=”25″ Width=”95%” OnPageIndexChanging=”gvProductOptions_PageIndexChanging”
OnSorting=”gvProductOptions_Sorting”>
<Columns>
<asp:BoundField HeaderText=”Option Title” DataField=”OptionTitle” SortExpression=”OptionTitle”
FooterText=”Total” FooterStyle-Font-Bold=”true” ItemStyle-HorizontalAlign=”Center”/>
<asp:BoundField HeaderText=”Quantity” DataField=”Quantity” SortExpression=”Quantity”/>
<asp:BoundField HeaderText=”Price” DataField=”Price” SortExpression=”Price” ItemStyle-HorizontalAlign=”Center” />
<asp:BoundField HeaderText=”Total Discount” DataField=”TotalDiscount” SortExpression=”TotalDiscount”
ItemStyle-HorizontalAlign=”Center” />
<asp:BoundField HeaderText=”Total BeforeDiscount” DataField=”TotalBeforeDiscount”
SortExpression=”TotalBeforeDiscount” ItemStyle-HorizontalAlign=”Center” />
<asp:TemplateField HeaderText=”Discounted Total” FooterStyle-Font-Bold=”True”>
<ItemTemplate>
<asp:Label ID=”lblDiscountTotal” runat=”server” Text=’<%# GetUnitPrice(DataBinder.Eval(Container.DataItem,”DiscountedTotal”)).ToString(“N2″)%>’></asp:Label>
</ItemTemplate>
<FooterTemplate>
<asp:Label ID=”lblTotal” runat=”server” Text=’<%# GetTotal().ToString(“N2″) %>’></asp:Label>
</FooterTemplate>
</asp:TemplateField>
<asp:BoundField HeaderText=”Organisation Name” DataField=”OrgName” SortExpression=”OrgName”
ItemStyle-HorizontalAlign=”Center” />
</Columns>
<EmptyDataTemplate>
No records available
</EmptyDataTemplate>
<EmptyDataRowStyle CssClass=”EmptyDataRowStyle” />
<FooterStyle CssClass=”FooterStyle” />
<RowStyle CssClass=”RowStyle” />
<EditRowStyle CssClass=”EditRowStyle” />
<SelectedRowStyle CssClass=”SelectedRowStyle” />
<PagerStyle CssClass=”PagerStyle” />
<HeaderStyle CssClass=”HeaderStyle” />
<AlternatingRowStyle CssClass=”AlternatingRowStyle” />
<PagerSettings FirstPageText=”First” LastPageText=”Last” NextPageText=”Next” PreviousPageText=”Previous”
Mode=”NextPreviousFirstLast” />
</asp:GridView>
</td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:TemplateField>
</Columns>
<EmptyDataTemplate>
No records available
</EmptyDataTemplate>
<EmptyDataRowStyle ForeColor=”black” BackColor=”white” />
</asp:GridView>
</div>
<br />
<p>
<asp:Button ID=”btnExportToExcel” runat=”server” Text=”Export” Visible=”false” OnClick=”btnExportToExcel_Click” />
</p>
<p>
<asp:Label ID=”lblError” runat=”server” CssClass=”ErrorText”></asp:Label>
</p>

Code behind file:

Paste the following code

#region btnExportToExcel_Click Event Start
protected void btnExportToExcel_Click(object sender, EventArgs e)
{
Export(“SalesReport.xls”, gvProducts, “Sales Report”);
}
#endregion btnExportToExcel_Click Event End

#region ExportToExcle Methods Start

public static void Export(string fileName, GridView gv, string title)
{
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.AddHeader(“content-disposition”, string.Format(“attachment; filename={0}”, fileName));
HttpContext.Current.Response.ContentType = “application/vnd.xls”;

using (StringWriter sw = new StringWriter())
{
HtmlTextWriter htw = new HtmlTextWriter(sw);
try
{
// render the table into the htmlwriter
RenderGrid(gv).RenderControl(htw);
// render the htmlwriter into the response
HttpContext.Current.Response.Write(“” + title + “”);
HttpContext.Current.Response.Write(“<br/><br/>”);
HttpContext.Current.Response.Write(“Report created at: ” + DateTime.Now.ToString());
//HttpContext.Current.Response.Write( System.Web.HttpUtility.HtmlDecode( sw.ToString()));
HttpContext.Current.Response.Write(sw.ToString());
HttpContext.Current.Response.End();
}
catch (System.Threading.ThreadAbortException lException)
{
// do nothing
}
finally
{
htw.Close();
}
}
}

private static Table RenderGrid(GridView grd)
{
// Create a form to contain the grid
Table table = new Table();
table.GridLines = grd.GridLines;

// add the header row to the table
if (grd.HeaderRow != null)
{
PrepareControlForExport(grd.HeaderRow);
table.Rows.Add(grd.HeaderRow);
}

// add each of the data rows to the table
foreach (GridViewRow row in grd.Rows)
{
//to allign top
row.VerticalAlign = VerticalAlign.Top;
row.HorizontalAlign = HorizontalAlign.Right;
PrepareControlForExport(row);
table.Rows.Add(row);
}

// add the footer row to the table
if (grd.FooterRow != null)
{
grd.FooterRow.HorizontalAlign = HorizontalAlign.Right;
PrepareControlForExport(grd.FooterRow);
table.Rows.Add(grd.FooterRow);
}
return table;
}

private static void PrepareControlForExport(Control control)
{
for (int i = 0; i < control.Controls.Count; i++)
{
Control current = control.Controls[i];
if (current is GridView)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, RenderGrid((GridView)current));
}
if (current is LinkButton)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl(string.Empty));
}
if (current is Button)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as Button).Text));
}
else if (current is ImageButton)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as ImageButton).AlternateText));
}
else if (current is Label)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as Label).Text));
}
else if (current is HyperLink)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as HyperLink).Text));
}
else if (current is DropDownList)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as DropDownList).SelectedItem.Text));
}
else if (current is CheckBox)
{
control.Controls.Remove(current);
control.Controls.AddAt(i, new LiteralControl((current as CheckBox).Checked ? “Da” : “Nu”));
}

if (current.HasControls())
{
PrepareControlForExport(current);
}
}
}

#endregion ExportToExcle Methods End

This should allow you to export the nested gridview to excel.

Happy coding……………………..

In order to achieve this first, you need to add a component known as Excel.dll (Microsoft excel 11.0 Object Library) into your .NET project references.

To do above follow below instructions:

Add a reference to the Microsoft Excel Object Library. To do this, follow these steps:

a. On the Project menu, click Add Reference.

b. On the COM tab, locate Microsoft Excel 11.0 Object Library, and then click Select.

c. Click OK in the Add References dialog box to accept your selections. If you receive a prompt to generate wrappers for the libraries that you selected, click yes.

The codes of the function to export data to Excel file is like below:-

private void ExportToExcelFile(System.Data.DataTable dt)

{

Excel.Application xlsApp = new Excel.ApplicationClass();

Excel.Workbook xlsWorkbook;

Excel.Worksheet xlsWorksheet;

string strhdr;

int row;

string strFile = “file1.xls”;

string filename = Server.MapPath(strFile);

if (dt.Rows.Count > 0)

{

//Create new workbook

xlsWorkbook = xlsApp.Workbooks.Add(true);

//Get the first worksheet

xlsWorksheet = (Excel.Worksheet)(xlsWorkbook.Worksheets[1]);

//Activate current worksheet

xlsWorksheet.Activate();

//Set header row to row 1

row = 1;

//Add table headers to worksheet

xlsWorksheet.Cells[row, 1] = “Enquiry Type”;

xlsWorksheet.Cells[row, 2] = “Topic Area”;

xlsWorksheet.Cells[row, 3] = “Status”;

xlsWorksheet.Cells[row, 4] = “Received Date”;

xlsWorksheet.Cells[row, 5] = “Enquiry”;

xlsWorksheet.Cells[row, 6] = “Customer Name”;

xlsWorksheet.Cells[row, 7] = “Agency location”;

xlsWorksheet.Cells[row, 8] = “Timetaken”;

//Format header row (bold, extra row height, autofit width)

xlsWorksheet.get_Range(“A” + row.ToString(), “C” + row.ToString()).Font.Bold = true;

xlsWorksheet.get_Range(“A” + row.ToString(), “C” + row.ToString()).Rows.RowHeight = 1.5 * xlsWorksheet.StandardHeight;

xlsWorksheet.get_Range(“A” + row.ToString(), “C” + row.ToString()).EntireRow.AutoFit();

//Freeze the columm headers

xlsWorksheet.get_Range(“A” + (row + 1).ToString(), “C” + (row + 1).ToString()).Select();

xlsApp.ActiveWindow.FreezePanes = true;

//Write data to Excel worksheet

foreach (DataRow dr in dt.Rows)

{

row += 1;

if (dr["Enquiry_type"] != null)

xlsWorksheet.Cells[row, 1] = dr["Enquiry_type"];

if (dr["Topic_area"] != null)

xlsWorksheet.Cells[row, 2] = dr["Topic_area"];

if (dr["Status"] != null)

xlsWorksheet.Cells[row, 3] = dr["Status"];

if (dr["Entered_DateTime"] != null)

xlsWorksheet.Cells[row, 4] = dr["Entered_DateTime"];

if (dr["Enquiry_Description"] != null)

xlsWorksheet.Cells[row, 5] = dr["Enquiry_Description"];

if (dr["Firstname"] != null)

xlsWorksheet.Cells[row, 6] = dr["Firstname"];

if (dr["Agency_Location"] != null)

xlsWorksheet.Cells[row, 7] = dr["Agency_Location"];

if (dr["TimeTaken"] != null)

xlsWorksheet.Cells[row, 8] = dr["TimeTaken"];

}

//Format data rows (align to center and left, autofit width and height)

xlsWorksheet.get_Range(“A2″, “C” + row.ToString()).VerticalAlignment = Excel.XlVAlign.xlVAlignCenter;

xlsWorksheet.get_Range(“A2″, “C” + row.ToString()).HorizontalAlignment = Excel.XlHAlign.xlHAlignLeft;

xlsWorksheet.get_Range(“A2″, “c” + row.ToString()).EntireColumn.AutoFit();

xlsWorksheet.get_Range(“A2″, “c” + row.ToString()).EntireRow.AutoFit();

//Make excel workbook visible to user after all data has been added to worksheet.

xlsApp.DisplayAlerts = false;

xlsWorkbook.Close(true, filename, null);

//Export data to client machine

strhdr = “attachment;filename=” + strFile;

Response.Clear();

Response.ContentType = “application/vnd.ms-excel”;

Response.ContentEncoding = System.Text.Encoding.Default;

Response.AppendHeader(“Content-Disposition”, strhdr);

Response.WriteFile(filename);

Response.Flush();

Response.Clear();

Response.Close();

}

}

Happy Coding……………………

<script type=”text/javascript”>

var handleTabChange = true;

function ValidatePage()

{

if(handleTabChange)

{

if (Page_ClientValidate(‘Tab1′) == false)

{

$find(“<%=TabContainerAddEnquiry.ClientID%>”).set_activeTabIndex(0);

}

else if (Page_ClientValidate(‘Tab2′) == false)

{

$find(“<%=TabContainerAddEnquiry.ClientID%>”).set_activeTabIndex(1);

}

else if (Page_ClientValidate(‘Tab3′) == false)

{

$find(“<%=TabContainerAddEnquiry.ClientID%>”).set_activeTabIndex(2);

}

}

else

{

handleTabChange = true;

}

}

</script>

From the above JavaScript you can see iam having if else statements and in that iam checking Page_ClientValidate() by passing the validation group of each and every tabpanel.

Iam having 3 tabpanels and evry tabpanel has got its own validation group set as you can see below highlighted with yellow Color. So basically you have to set separate validation group for each and every tabcontrol.

See source code here:

<EA:TabContainer ID=”TabContainerAddEnquiry” runat=”server” CssClass=”scienceEnquiry” OnClientActiveTabChanged=”SaveActiveTabIndex” ActiveTabIndex=”1″>

<EA:TabPanel ID=”tabContactDetails” runat=”server” HeaderText=”Contact Details” TabIndex=”1″>

<ContentTemplate>

<p>

<label for=”Textbox1″>

Text1:

</label>

<asp:TextBox ID=”Textbox1″ runat=”server” TextMode=”MultiLine” ValidationGroup=”Tab1″></asp:TextBox>

<asp:RequiredFieldValidator ID=”_ Textbox1ReqFieldVal” runat=”server” ControlToValidate=”Textbox1″ ValidationGroup=”Tab1″

SetFocusOnError=”True” Display=”None” ErrorMessage=”<b>Required Field Missing</b><br />Recieved Date is required.”></asp:RequiredFieldValidator>

<EA:ValidatorCalloutExtender ID=”_ Textbox1DescValExt” TargetControlID=”_Textbox Textbox1ReqFieldVal “

HighlightCssClass=”validatorCalloutHighlight” runat=”server” Enabled=”True”>

</EA:ValidatorCalloutExtender>

</p>

</ContentTemplate>

</EA:TabPanel>

<EA:TabPanel ID=”tabEnquiryDetails” runat=”server” HeaderText=”Enquiry Details” TabIndex=”2″>

<ContentTemplate>

<p>

<label for=”Textbox2″>

Text2:

</label>

<asp:TextBox ID=”Textbox2″ runat=”server” TextMode=”MultiLine” ValidationGroup=”Tab2″></asp:TextBox>

<asp:RequiredFieldValidator ID=”_ Textbox2ReqFieldVal” runat=”server” ControlToValidate=”Textbox2″ ValidationGroup=”Tab2″

SetFocusOnError=”True” Display=”None” ErrorMessage=”<b>Required Field Missing</b><br />Recieved Date is required.”></asp:RequiredFieldValidator>

<EA:ValidatorCalloutExtender ID=”_ Textbox1DescValExt” TargetControlID=”_ Textbox2ReqFieldVal “

HighlightCssClass=”validatorCalloutHighlight” runat=”server” Enabled=”True”>

</EA:ValidatorCalloutExtender>

</p>

</ContentTemplate>

</EA:TabPanel>

<EA:TabPanel ID=”tabAssignTo” runat=”server” HeaderText=”Assign To” TabIndex=”3″>

<ContentTemplate>

<p>

<label for=”Textbox3″>

Text3:

</label>

<asp:TextBox ID=”Textbox3″ runat=”server” TextMode=”MultiLine” ValidationGroup=”Tab3″></asp:TextBox>

<asp:RequiredFieldValidator ID=”_ Textbox3ReqFieldVal” runat=”server” ControlToValidate=”Textbox3″ ValidationGroup=”Tab3″

SetFocusOnError=”True” Display=”None” ErrorMessage=”<b>Required Field Missing</b><br />Recieved Date is required.”></asp:RequiredFieldValidator>

<EA:ValidatorCalloutExtender ID=”_ Textbox3DescValExt” TargetControlID=”_Textbox3ReqFieldVal “

HighlightCssClass=”validatorCalloutHighlight” runat=”server” Enabled=”True”>

</EA:ValidatorCalloutExtender>

</p>

</ContentTemplate>

</EA:TabPanel>

</EA:TabContainer>

And after setting the validation groups, I need to validate the data when in click on the submit button. So in order to validate the data in button click there is a property called OnClientClick for button control . Use this property to call the javascript like this =”javascript:ValidatePage();” and one more thing you need to do is set the validation groups for the button control as shown below:

<asp:Button ID=”_btnSubmit” runat=”server” Text=”Add Enquiry” CausesValidation=”true” ValidationGroup=”Tab1,Tab2,Tab3″ OnClick=”_btnSubmit_Click” OnClientClick=”javascript:ValidatePage();” />

This solves the problem. Happy Coding…………..

protected void _btnReports_Click(object sender, EventArgs e)

{

Response.Clear();

Response.Write(@”<!DOCTYPE HTML PUBLIC “”-//W3C//DTD HTML 4.0 Transitional//EN”">”);

Response.AddHeader(“content-disposition”, “inline;filename=search_topicarea.doc”);

Response.Charset = “”;

Response.Cache.SetCacheability(HttpCacheability.NoCache);

Response.ContentType = “application/vnd.doc”;

System.IO.StringWriter stringWrite = new System.IO.StringWriter();

//System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

//Render(htmlWrite);

_gvViewresults.RenderControl(htmlWrite);

Response.Write(stringWrite.ToString());

Response.End();

}

And adding a little piece of code like override the Page.VerifyRenderingInServerForm method as shown below

public override void VerifyRenderingInServerForm(Control control)

{

// Confirms that an HtmlForm control is rendered for the

//specified ASP.NET server control at run time.

}

But this works in aspx page but you cannot override the Page.VerifyRenderingInServerForm method in the web user control.

In order to solve the above problem:

1. Create one aspx page

2. Then drag the web user control in to this aspx page but your grid view and the button click events will be in the web user control only.

3. Then in the aspx page in the Page directives tag just add EnableEventValidation=”false”.

4. In the code behind file i.e. aspx.cs file now override the Page.VerifyRenderingInServerForm method.

5. This works.

Sample code is given below:

<%@ Page Language=”C#” MasterPageFile=”~/Masters/abc.master” AutoEventWireup=”true”

CodeFile=”create.aspx.cs” Inherits=”abc_ create “ EnableEventValidation=”false”

Title=”create” %>

<%@ Register Src=”../UserControls/View.ascx” TagName=”View” TagPrefix=”uc1″ %>

<%@ Register Assembly=”AjaxControlToolkit” Namespace=”AjaxControlToolkit” TagPrefix=”EA” %>

<asp:Content ID=”Content1″ ContentPlaceHolderID=”MainContent” runat=”Server”>

<h2 class=”blue”>

View Pending Enquiries

</h2>

<p>

<uc1: View id=”_View” runat=”server”>

</uc1: View ></p>

</asp:Content>

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using EA.SEDB.BO.ScienceEnquiriesDBTableAdapters;

using EA.SEDB.BO;

using EA.SEDB.BS;

public partial class abc_view : System.Web.UI.Page

{

#region Declare Variables Start

Abc.UsersDataTable UsersDT = null;

string userName = string.Empty;

int loggedInUserId;

#endregion Declare Variables End

#region PageLoad Start

protected void Page_Load(object sender, EventArgs e)

{

userName = HttpContext.Current.User.Identity.Name;

if (!Page.IsPostBack)

{

if (!string.IsNullOrEmpty(userName))

{

UsersDT = Administration.GetUserDetailsByUsername(userName);

if (UsersDT.Rows.Count > 0)

{

loggedInUserId = UsersDT[0].UserId;

}

}

if (HttpContext.Current.User.Identity.IsAuthenticated)

{

if (Roles.IsUserInRole(ConfigurationManager.AppSettings["Managers"]))

{

_ViewEnquiries.ViewEnquiries_ForManager(loggedInUserId, ConfigurationManager.AppSettings["AssignTo"].ToString());

}

else if (Roles.IsUserInRole(ConfigurationManager.AppSettings["TeamMembers"]))

{

_ViewEnquiries.ViewEnquiries_ForTeamMember(loggedInUserId, ConfigurationManager.AppSettings["Assign"].ToString());

}

else

{

Response.Redirect(“~/UnauthorisedPage.aspx”);

}

}

else

{

Response.Redirect(“~/UnauthorisedPage.aspx”);

}

}

}

public override void VerifyRenderingInServerForm(Control control)

{

// Confirms that an HtmlForm control is rendered for the

//specified ASP.NET server control at run time.

}

#endregion PageLoad End

}

Happy Coding…….

Exporting Grid View to Excel Files:

The approach is pretty much the same as it was in Gridview. The following code executes on a button click event.

protected void _btnReports_Click(object sender, EventArgs e)

{

Response.Clear();

Response.Write(@”<!DOCTYPE HTML PUBLIC “”-//W3C//DTD HTML 4.0 Transitional//EN”">”);

Response.AddHeader(“content-disposition”, “inline;filename=search_topicarea.doc”);

Response.Charset = “”;

Response.Cache.SetCacheability(HttpCacheability.NoCache);

Response.ContentType = “application/vnd.doc”;

System.IO.StringWriter stringWrite = new System.IO.StringWriter();

//System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

System.Web.UI.HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);

//Render(htmlWrite);

_gvViewresults.RenderControl(htmlWrite);

Response.Write(stringWrite.ToString());

Response.End();

}

The above shown code is almost identical to what we normally use when exporting Gridview to some other formats. But if you run this code it will not work, the reason is that we need to tell ASP.NET that there is a control in our form that will be rendered at runtime.

In order to work the above shown code you need to add some piece of code as shown below i.e just override the Page.VerifyRenderingInServerForm method.

public override void VerifyRenderingInServerForm(Control control)

{

// Confirms that an HtmlForm control is rendered for the

//specified ASP.NET server control at run time.

}

Now if you try to export your GridView to excel it will work fine.

Happy Coding……….

In this article you can see how to work with XML documents with the help of ADO.NET. In this there are two approaches to work with XML and ADO.

1. You can use ADO.NET to access XML documents.

2. You can use ADO.NET and XML to access XML. Apart from this, you can access RDBMS using ADO.NET and XML.NET.

First we will see how to read XML using a Dataset

Reading XML using a Dataset

Normally in ADO.NET, we can access the data using the Dataset class. The Dataset class implements methods and properties to work with XML documents.

In this article first we discuss the methods that read XML data.

ReadXml Method

ReadXml is used to read a data stream or an XML file and to store into a Dataset object, later which can be used to display the data in a tabular format. ReadXmlmethod has eight overloaded forms. ReadXML can read a text, string, stream, TextReader, XmlReader, and combination formats. In the following example, first we create a new DataSet object as follows:

DataSet ds = new DataSet();

After creating a dataset object we will call the ReadXML method to read the xml file into the dataset as follows

// Fill with the data

ds.ReadXml(“books.xml “);

We should remember one thing when we are working with Datasets we have to add some references like some namespaces

System.Data

System.Data.Common

Now we are going to see how the ReadXmlSchema method works

ReadXmlSchema method

Basically ReadXMLSchema method reads an XML schema in a DataSet object. You can use a string, stream,Text Reader and XmlReader.

In the below example we will see how to read a file using ReadXmlSchema.

First create an object for the dataset

DataSet ds = new DataSet( );

Then using the ReadSchema method read the XML file like this

ds.ReadSchema (@”c:\books. xml”);

See the below example which uses XMLTextReader as input of ReadXmlSchema

DataSet ds = new DataSet(“New DataSet”);

// Now we are going to read xml using XmlTextReader as follows

XmlTextReader objXmlReader = new XmlTextReader(@”c:\books.Xml”);

//Now Call Read xml schema method which takes the parameter as XmlTextReader

ds.ReadXmlSchema(objXmlReader);

//Now close the XmlTextReader

objXmlReader.Close();

Writing XML using a Dataset

Dataset class not only contains methods to read the data but still it has got methods to write XML file from dataset in to the file also. Now we will see writeXml method.

WriteXml Method

WriteXml method is used to write the data from Datasetto an XML file. By using WriteXml method, you can write data to a file, stream, TextWriter, or XmlWriter. In this example let’s creates a Dataset and fills the corresponding data into the Dataset, and then writes the data into an XML file. Below is the example for WriteXml Method.

Using System;

Using System.IO;

Using System.Xml;

Using System.Data;

Namespace XmlDataset

{

Class XmlDataset

{

Public static void Main ()

{

DataSet ds = new DataSet(“DataSet”);

ds.Namespace = “EmpNamespace”;

//Now create DataTable and add columns to the datatable

DataTable dt = new DataTable(“Employee”);

DataColumn col1 = new DataColumn(“Name”);

DataColumn col2 = new DataColumn(“Address”);

dt.Columns.Add(col1);

dt.Columns.Add(col2);

ds.Tables.Add(dt);

//Add Employee Data to the table

//Create a new row and add the data to the corresponding columns

DataRow dr; dr = dt.NewRow();

dr ["Name"] = “Rajesh”;

dr ["Address"] = “Hagley Road”;

dt.Rows.Add(dr);

dr = dt.NewRow();

dr ["Name"] = “Tim Easton”;

dr ["Address"] = “London”;

dt.Rows.Add(dr);

dr = dt.NewRow();

dr ["Name"] = “Sara”;

dr ["Address"] = “Oxford”;

// Now add the datarows to the datatable

dt.Rows.Add(dr);

// After adding the rows to the datatable use AcceptChanges method if there are any changes

ds.AcceptChanges();

//Now order to stored the data in Xml File, we create a new StreamWriter and then save the data in to the Xml file as follows

StreamWriter myStreamWriter = new

StreamWriter(@”c:\xmldata.xml”);

// Now for the dataset use the writeXml method which writes the data from dataset to Xml file, it takes the parameter as streamwriter

// It writes the data in to the xml file

ds.WriteXml(myStreamWriter);

myStreamWriter.Close();

return;

}

}

}

Now in order to see the output of this program, open the xmldata.xml file. You can see the standard XML file as shown below.

Output for WriteXml method

-<DataSet xmlns=” EmpNamespace “>

- <Student>

<Name>Rajesh</Name>

<Address>Hagley Road</Address>

</Student>

- <Student>

<Name>Tim Easton</Name>

<Address>London</Address>

</Student>

- <Student>

<Name>Sara</Name>

<Address>Oxford</Address>

</Student>

</DataSet >

Now we will see the Write Xml Schema method how it works.

Write xml schema method

Write xml schema method writes the dataset structure into an XML schema. Using this method you can write the data to a stream, text, TextWriter, or Xmlwriter.

Below is the example for the write xml schema.

// Create object for the dataset

DataSet ds = new DataSet(“DataSet”);

ds.Namespace = “EmpNamespace”;

//Now create DataTable and add columns to the datatable

DataTable dt = new DataTable(“Employee”);

DataColumn col1 = new DataColumn(“Name”);

DataColumn col2 = new DataColumn(“Address”);

dt.Columns.Add(col1);

dt.Columns.Add(col2);

ds.Tables.Add(dt);

//Add Employee Data to the table

//Create a new row and add the data to the corresponding columns

DataRow dr; dr = dt.NewRow();

dr ["Name"] = “Rajesh”;

dr ["Address"] = “Hagley Road”;

dt.Rows.Add(dr);

dr = dt.NewRow();

dr ["Name"] = “Tim Easton”;

dr ["Address"] = “London”;

dt.Rows.Add(dr);

dr = dt.NewRow();

dr ["Name"] = “Sara”;

dr ["Address"] = “Oxford”;

// Now add the datarows to the datatable

dt.Rows.Add(dr);

// After adding the rows to the datatable use AcceptChanges method if there are any changes

ds.AcceptChanges();

// Now create an object for the xmlTextWriter

XmlTextWriter writer = new XmlTextWriter(Console.Out);

// using the writeXmlSchema method write the data

ds.WriteXmlSchema(writer);

Now we will see about the XmlDataDocumet

What is XmlDataDocument?

XmlDataDocument is a class defined within the System.Xml namespace. Basically it extends the XmlDocument class. The XmlDataDocument class allows the information stored within a DataSet to be treated as XML. Using this class, developers can manipulate data stored within a DataSet as XML or relational data.

Load and LoadXml from the XmlDataDocument

In order to load the data in to xmlDataDocument either you can user Load method or the LoadXmlmethod. The difference between Load and LoadXml is Load method takes the parameter as a filename string or TextReader. But in the case of LoadXml it takes an Xml file. For better explanation see the below example.

// Now create an object for the XmlDataDocument

XmlDataDocument doc = new XmlDataDocument( );

// Now using Load method load the xml file in to the document

doc.Load(“c:\\ Employees.xml”);

Now see how to load xml file using LoadXml

XmlDataDocument doc = new XmlDataDocument( );

doc.LoadsXml (“<Name> Abc </ Name>”);

How to Load Data Using a DataSet

Now we will see how to load data using DataSet. Dataset object has methods to read XML documents. These methods to read Xml documents are ReadXmlSchema and LoadXml.

See the below example how to read xml schema and how to read xml file

First create object for the XmlDataDocument

XmlDataDocument doc = new XmlDataDocument( );

doc.DataSet.ReadXmlSchema (“test. Xsd”);

Or

doc.DataSet.ReadXml (“<Name> Abc </ Name >”);

How to Displaying XML Data In a DataSet Format?

Now you can get DataSet object from an XmlDataDocument object by using its DataSet property. In order to read XML document in a dataset, first of all we have to read data into document. We can read a document using the ReadXml method of the DataSet object. You can see in the below example.

XmlDataDocument xmlDocument = new XmlDataDocument();

xmlDocument.DataSet.ReadXml (“c:\\ document.xml”);

// In order to see the data in the dataset just bind the xmldocument to the gridview by using DefaultViewManager propety in the dataset.

GridView1.DataSource = xmlDocument.DataSet.DefaultViewManager;

If you need the complete code for this you can see below:

Public Data ( )

{

//Now create an XmlDataDocument object and read an XML file

XmlDataDocument xmldoc = new XmlDataDocument();

xmldoc.DataSet.ReadXml(“C:\\books.xml”);

// Create a DataSet object and fill with the dataset

// of XmlDataDocument

DataSet ds = new DataSet(“Books DataSet”);

ds = xmldoc.DataSet;

// Attach dataset view to the GridView control

GridView1.DataSource = ds.DefaultViewManager;

}

Now See how to Save Data from DataSet to XML ?

Now you will see how to save data form dataset to xml. In this you can save data of a DataSet as an XML document using the Save method of XmlDataDocument. Actually the XmlDocument class defines the Save method.

Now create a DataSet object and fill it using a DataAdapter. The below shown example reads the Employees table from the Northwind Oracle database and fills the data into the DataSet.

// write the select query which details you want to retrive from database

string query = “SELECT * FROM Employees”;

// Give the connection string i.e connection to the database

string connString =

“Data Source=NorthWind.mdb; User ID=scott; Password=tiger”;

// Create an object for the oracle data adapter and pass the quey and the connection string to the adapter

OracleDataAdapter objAdapter = new OracleDataAdapter(query, connString);

// Now the adaptor will get the data and whe have to store the data

//So create a new dataset object and fill the dataset by using data adapter’s fill method

DataSet ds = new DataSet();

objAdapter.Fill(ds);

Now, you create an instance of XmlDataDocument with the DataSet as an argument and call the Save method to save the data as an XML document:

XmlDataDocument doc = new XmlDataDocument(ds);

doc.Save(“C:\\XmlData.xml”);

Thats it and happy coding…………………….

Error Page

Basically this error occurs when a code block is placed in the MasterPage like this

<%@  Master Language=”C#” AutoEventWireup=”True” Inherits=”TrainingWeb” CodeBehind=”TrainingWeb.master.cs” %>

<%@ Register Src=”UserControls/TopMenu.ascx” TagName=”TopMenu” TagPrefix=”uc1″ %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN” “http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml”>

<head id=”Head1″ runat=”server”>

    <meta http-equiv=”Content-Type” content=”text/html; charset=iso-8859-1″ />

    <title></title>

    <link href=”styles.css” rel=”stylesheet” type=”text/css” />

    <script language=”JavaScript” src=’<%= ResolveClientUrl(“~/mm_menu.js”)%>‘></script>

</head>

<body>

    <form id=”form1″ runat=”server”>  

    <asp:ContentPlaceHolder ID=”ContentPlaceHolder1″ runat=”server”>   

    </asp:ContentPlaceHolder>

    </form>

</body>

</html>

As you can see from the above code with the highlited colour if you mention the code block like this you can get the above error.

SOLUTION:

In order to avoid this error just  copy the codeblock from the head tag to the content place holder in the master page like this

<%@  Master Language=”C#” AutoEventWireup=”True” Inherits=”TrainingWeb” CodeBehind=”TrainingWeb.master.cs” %>

<%@ Register Src=”UserControls/TopMenu.ascx” TagName=”TopMenu” TagPrefix=”uc1″ %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN” “http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

<html xmlns=”http://www.w3.org/1999/xhtml”>

<head id=”Head1″ runat=”server”>

    <meta http-equiv=”Content-Type” content=”text/html; charset=iso-8859-1″ />

    <title></title>

    <link href=”styles.css” rel=”stylesheet” type=”text/css” />

</head>

<body>

    <form id=”form1″ runat=”server”>

    <asp:ContentPlaceHolder ID=”ContentPlaceHolder1″ runat=”server”>

    <script language=”JavaScript” src=’<%= ResolveClientUrl(“~/mm_menu.js”)%>‘></script>

    </asp:ContentPlaceHolder>

    </form>

</body>

</html>

This solves the problem.

WCF follows an asynchronous messaging. It makes extensive use of asynchronous I/O, and as a result, each received message may be dispatched to a receiving object by different threads. Because of this feature allows WCF to use the CPU efficiently, and as a result, allows WCF applications to scale.

Below given example make clear the concurrence mode instance, how service class works with ConcurrencyMode instance property on the ServiceBehaviorAttribute type with respect to the client requests.

Types of modes:

Single: only one thread will access the incoming object at a time

Multiple: multiple threads will access the incoming object concurrently

Reentrant: only one thread will access the incoming object at a time, but callbacks will re-enter that object on another thread  

The service class specifies ConcurrencyMode as    

// Single mode will use the same instance for all the clients concurrently

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple,InstanceContextMode = InstanceContextMode.Single)] 

// PerCall will use the same instance for all the clients concurrently

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.PerCall)] 

// Multiple mode will use the multiple instance for the clients concurrently

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.Single)] 

//Reentrant mode will use to call other method of another object (if required), which is not allowed in Single

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Reentrant, InstanceContextMode = InstanceContextMode.Single)] 

The service class contains the following

1.      Constructor, which is useful to create new GUID for every instance of service class

2.      getInfo(), returns message to the client

3.      getInfo2(), returns message to the client 

Implementation Steps follows as below 

1)     Create new WCF Service Library Project with the name WCFLib

2)     Rename Iservice.cs to IServicedClass.cs from Solution Explorer

3)     Rename Service.cs to ServicedClass.cs from Solution Explorer

4)     Add Reference to System.ServiceModel from Solution Explorer

5)     Write the following code in IServicedClass.cs 

using System.ServiceModel; 

namespace WCFLib

{

    [ServiceContract]

    public interface IServicedClass

    {

        [OperationContract]

        string getInfo();

        [OperationContract]

        string getInfo2();

    }

} 

6)     Write the following code in ServicedClass.cs 

using System.ServiceModel;

using System.Threading; 

namespace WCFLib

{

     /* Concurrency Start */

    // Single mode will use the same instance for all the clients concurrently

    //to see run 2 client programs

      [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple,

          InstanceContextMode = InstanceContextMode.Single)]

   /* Concurrency End */   

    public class ServicedClass:IServicedClass

    {

        private Guid id;

        public ServicedClass()

        {

            id = Guid.NewGuid();

        } 

        public string getInfo()

        {

            Thread.Sleep(3000);

            return “*** getInfo called on Object id : “ + id.ToString() + “***”;

        } 

        [OperationBehavior]

        public string getInfo2()

        {

            return “*** getInfo2 called on Object id : “ + id.ToString() + “***”;

        }

    }

}  

Note : Rebuild the service (WCFLib project) after changing the ServiceBehavior for concurrence instance.  

7)     Build only WCFLib project

     Add new Console Application with the name  WCFSerCon in the solution

9)     Add Reference to System.ServiceModel

10) Add Reference to WCFLib.dll

11) Write the following code in Program.cs 

using System.ServiceModel;

using WCFLib; 

namespace WCFSerCon

{

    class Program

    {

        static void Main(string[] args)

        {

            ServiceHost host = new ServiceHost(typeof(ServicedClass));

            string address = “net.tcp://localhost:1099/Myobject”;

            NetTcpBinding binding = new NetTcpBinding();

            host.AddServiceEndpoint(typeof(IServicedClass), binding, address);

            host.Open();

            Console.WriteLine(“Server is Read and Running…”);

            Console.ReadLine(); 

        }

    }

} 

12) Build only WCFSerCon project

13) Add new Console Application with the name  WCFClientCon in the solution

14) Add Reference to System.ServiceModel

15) Add Reference to WCFLib.dll

16) Write the following code in Program.cs 

using System.Threading;

using System.ServiceModel;

using WCFLib; 

namespace WCFClientCon

{

    class Program

    {

        static void Main(string[] args)

        {

            string address = “net.tcp://localhost:1099/Myobject”;

            NetTcpBinding binding = new NetTcpBinding();

            ChannelFactory<IServicedClass> cf = new ChannelFactory<IServicedClass>(binding, address);

            IServicedClass obj = cf.CreateChannel();

         //Concurrancy example

            for (int i = 0; i < 10; i++)

            {

                Console.Write(DateTime.Now.ToLongTimeString());

                Console.WriteLine(obj.getInfo());

                Thread.Sleep(1000);

                Console.WriteLine(obj.getInfo2());

            } 

            Console.WriteLine();

            Console.WriteLine(“Press any key…”);

            Console.ReadLine(); 

        }

    }

} 

17) Build only WCFClientCon project

18) Set WCFSerCon as start up project and Run using ctrl+F5

19) Now server is ready and you can find the following screen 

WCF-Concurrence Server Ready

20) Set WCFClientCon as start up project and Run using ctrl+F5

21) Now client application is executing and you can find the following output   

 i.e Single mode will use the same instance for all the clients concurrently  22) Instead of the above Service concurrence Mode, if we will write the following statement in   same file, WCFLib/ServicedClass.cs [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple, InstanceContextMode = InstanceContextMode.PerCall)] i.e.  PerCall will use the same instance for all the clients concurrently  We can get the following output  WCF Cconcurrence PerCall OutPut”]

WCF Concurrence- Single Output The service class specifies ConcurrencyMode as [ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Multiple,InstanceContextMode = InstanceContextMode.Single)

 

The newley introduced .NET Framework 3.5 with Visual Studio 2008  provides developers to rapidly create applications that deliver high quality and rich user experiences. Visual Studio 2008 and .NET 3.5 contains a ton of new functionality and improvements which enables organizations of every size to rapidly create secure, manageable, and reliable applications that are optimized for Windows Vista™, SQL Server and the Web.

Visual Studio .NET based Windows application benefits from increased WPF designer performance.  Web development improvements include enhanced features like JavaScript IntelliSense, JavaScript Debugging,supports SQL Server 2008, ADO.NET Entity Framework, ADO.NET Data Services. It provides more powerful new graphics for the development and provides very rich data scaffolding. 

The .NET 3.5 Framework SP1 delivers the following:

• Increased Performance for WPF based applications, without having to change any code
• WCF improvements that give developers more control over the way they access data and services
• Improvements such as the ADO.NET Data Services, ADO.NET Entity Framework  and support for SQL Server 2008
• ASP.NET Dynamic Data to facilitate rapid data driven development  

New Features of Visual studio 2008 and .Net 3.5:

1. Visual Studio 2008 Multi-Targeting Support.   

– .NET Framework 2.0, 3.0 and 3.5

2.VS 2008 CSS Web Designer and CSS Support

3.ASP.NET AJAX and JavaScript Support 

   . Visual Studio 2008 Javascript Intellisense
   • Visual Studio 2008 JavaScript Debugging.
   • Visual Studio 2008 CSS Web Designer and CSS Support
   • Visual Studio 2008 Vertical Split View Support

4.ADO.NET Entity Framework

5.ADO.NET Data Services

6.ASP.NET Dynamic Data Priview

7.Language Improvements and LINQ 

    • Anonymous Types
    • Extension Methods
    • Lambda Expressions
    . LINQ to Data Sets
    • LINQ to SQL
    • LINQ to XML
    • LINQ to Objects

 Some of Other Visual Studio 2008 Features are:   

    • In-built Silverlight Library
     . Windows Communication Foundation Support
    • Windows Presentation Foundation Support and WPF improvements
    • Inbuilt AJAX Extender Controls
    • Intellisense Improvements in visual studio 2008
    • In-built C++ SDK
    • Nested ASP.NET Master Pages