Sample :
HTML Code
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<!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">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<fieldset>
<legend>GridviewNestingDropdowlist</legend>
<asp:gridview id="gridview1" runat="server" autogeneratecolumns="False" onrowdatabound="gridview1_rowdatabound">
<columns>
<asp:boundfield datafield="user_email" headertext="email" />
<asp:boundfield datafield="user_name" headertext="user name" />
<asp:BoundField DataField="user_id" HeaderText="user id" />
<asp:templatefield headertext="products">
<itemtemplate>
<asp:dropdownlist id="dropdownlist1" runat="server">
</asp:dropdownlist>
</itemtemplate>
</asp:templatefield>
</columns>
</fieldset>
</form>
</body>
</html>
Behind Code
Imports System.Data.SqlClient
Imports System.Data
Partial Class _Default
Inherits System.Web.UI.Page
Dim dt As New System.Data.DataTable()
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
GridView1.DataSource = getdataset().Tables(0)
GridView1.DataBind()
End Sub
Private Function getdataset() As Data.DataSet
' Dim connectionstring As String = "Data Source=localhost;Initial Catalog=northwind;User ID=sa;password="
Dim connectionstring As String = " Your Connection "
Dim query As String = " Your query "
Dim myconnection As New System.Data.SqlClient.SqlConnection(connectionstring)
Dim ad As New System.Data.SqlClient.SqlDataAdapter(query, myconnection)
Dim ds As New Data.DataSet()
ad.Fill(ds)
Return ds
End Function
Protected Sub gridview1_rowdatabound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles gridview1.RowDataBound
Dim mytable As New Data.DataTable()
Dim productidcolumn As New Data.DataColumn("user_id")
Dim productnamecolumn As New Data.DataColumn("user_name")
mytable.Columns.Add(productidcolumn)
mytable.Columns.Add(productnamecolumn)
Dim ds As New Data.DataSet()
ds = getdataset()
Dim categoryid As String = ""
Dim expression As String = String.Empty
If e.Row.RowType = DataControlRowType.DataRow Then
expression = " user_email like '%W%'"
Dim ddl As DropDownList = CType(e.Row.FindControl("dropdownlist1"), DropDownList)
Dim rows As Data.DataRow() = ds.Tables(0).Select(expression)
Dim row As Data.DataRow
For Each row In rows
Dim newrow As Data.DataRow = mytable.NewRow()
newrow("user_id") = row("user_id")
newrow("user_name") = row("user_name")
mytable.Rows.Add(newrow)
Next row
ddl.DataSource = mytable
ddl.DataTextField = "user_name"
ddl.DataValueField = "user_id"
ddl.DataBind()
End If
End Sub
End Class
:thumbsup::D:D:D