I bet you must have seen this question asked a several times ‘How Can I find out which Checkboxes were selected in a GridView. I also want to retrieve row data for these selected rows on Postback’.
I personally have seen this question hundreds of times on the forums, newsgroups. If you have been facing this requirement, here’s a full working example for you to try out. This example binds the GridView to a List<>
<!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 runat="server">
<title>Get Selected Rows during PostBack</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false"
DataKeyNames="ID" >
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="chkSel" runat="server" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="ID" HeaderText="EmployeeId"
SortExpression="EmployeeId" />
<asp:BoundField DataField="FName" HeaderText="FirstName"
SortExpression="FirstName" />
<asp:BoundField DataField="Age" HeaderText="Age"
SortExpression="Age" />
<asp:BoundField DataField="Sex" HeaderText="Sex"
SortExpression="Sex" />
</Columns>
</asp:GridView>
<br />
<asp:Button ID="btnRetrieveCheck" runat="server"
Text="Retrieve Checked Items" onclick="btnRetrieveCheck_Click" />
</div>
</form>
</body>
</html>
Points to observe:
- The AutoGenerateColumns of the GridView is set to false
- The CheckBox has been added inside an ItemTemplate
- DataKeyName of the GridView is set to ID.
C#
using System;
using System.Collections.Generic;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Default4 : System.Web.UI.Page
{
List<Employee> listEmp = new List<Employee>();
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
Employee emp = new Employee();
listEmp = emp.GetEmployees();
this.GridView1.DataSource = listEmp;
this.GridView1.DataBind();
}
}
protected void btnRetrieveCheck_Click(object sender, EventArgs e)
{
foreach (GridViewRow row in GridView1.Rows)
{
CheckBox cb = (CheckBox)row.FindControl("chkSel");
if (cb != null && cb.Checked)
{
Response.Write("Employee Id: " +
GridView1.DataKeys[row.RowIndex].Value
+ " Name: " + row.Cells[2].Text + "<br/>");
}
}
}
}
public class Employee
{
public int ID { get; set; }
public string FName { get; set; }
public int Age { get; set; }
public char Sex { get; set; }
public List<Employee> GetEmployees()
{
List<Employee> eList = new List<Employee>();
eList.Add(new Employee() { ID = 1, FName = "John", Age = 23, Sex = 'M' });
eList.Add(new Employee() { ID = 2, FName = "Mary", Age = 25, Sex = 'F' });
eList.Add(new Employee() { ID = 3, FName = "Amber", Age = 23, Sex = 'M' });
eList.Add(new Employee() { ID = 4, FName = "Kathy", Age = 25, Sex = 'M' });
eList.Add(new Employee() { ID = 5, FName = "Lena", Age = 27, Sex = 'F' });
eList.Add(new Employee() { ID = 6, FName = "John", Age = 28, Sex = 'M' });
eList.Add(new Employee() { ID = 7, FName = "Kathy", Age = 27, Sex = 'F' });
eList.Add(new Employee() { ID = 8, FName = "John", Age = 28, Sex = 'M' });
return eList;
}
}
VB.NET
Imports System
Imports System.Collections.Generic
Imports System.Web.UI
Imports System.Web.UI.WebControls
Partial Public Class Default4
Inherits System.Web.UI.Page
Private listEmp As New List(Of Employee)()
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
If (Not Page.IsPostBack) Then
Dim emp As New Employee()
listEmp = emp.GetEmployees()
Me.GridView1.DataSource = listEmp
Me.GridView1.DataBind()
End If
End Sub
Protected Sub btnRetrieveCheck_Click(ByVal sender As Object, _
ByVal e As EventArgs)
For Each row As GridViewRow In GridView1.Rows
Dim cb As CheckBox = CType(row.FindControl("chkSel"), CheckBox)
If cb IsNot Nothing AndAlso cb.Checked Then
Response.Write("Employee Id: " & _
GridView1.DataKeys(row.RowIndex).Value & " Name: " & _
row.Cells(2).Text & "<br/>")
End If
Next row
End Sub
End Class
Public Class Employee
Private privateID As Integer
Public Property ID() As Integer
Get
Return privateID
End Get
Set(ByVal value As Integer)
privateID = value
End Set
End Property
Private privateFName As String
Public Property FName() As String
Get
Return privateFName
End Get
Set(ByVal value As String)
privateFName = value
End Set
End Property
Private privateAge As Integer
Public Property Age() As Integer
Get
Return privateAge
End Get
Set(ByVal value As Integer)
privateAge = value
End Set
End Property
Private privateSex As Char
Public Property Sex() As Char
Get
Return privateSex
End Get
Set(ByVal value As Char)
privateSex = value
End Set
End Property
Public Function GetEmployees() As List(Of Employee)
Dim eList As New List(Of Employee)()
eList.Add(New Employee() With {.ID = 1,.FName = "J",.Age = 23,.Sex = "M"c})
eList.Add(New Employee() With {.ID = 2,.FName = "M",.Age = 25,.Sex = "F"c})
eList.Add(New Employee() With {.ID = 3,.FName = "A",.Age = 23,.Sex = "M"c})
eList.Add(New Employee() With {.ID = 4,.FName = "K",.Age = 25,.Sex = "M"c})
eList.Add(New Employee() With {.ID = 5,.FName = "L",.Age = 27,.Sex = "F"c})
eList.Add(New Employee() With {.ID = 6,.FName = "J",.Age = 28,.Sex = "M"c})
eList.Add(New Employee() With {.ID = 7,.FName = "K",.Age = 27,.Sex = "F"c})
eList.Add(New Employee() With {.ID = 8,.FName = "J",.Age = 28,.Sex = "M"c})
Return eList
End Function
OUTPUT
