Check Uncheck all CheckBoxes in GridView and send checked column data to TextBox with comma separated using C# and VB.Net in ASP.Net

Hi prateekmj,

I have created sample that full fill your requirement.

You can manage in two different ways.

1. By calling with single Event.

HTML

<asp:GridView ID="gvcntct" runat="server" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="Sl. No." />
        <asp:BoundField DataField="Name" HeaderText="Contact Name" />
        <asp:BoundField DataField="Mobile" HeaderText="Mobile Number" />
        <asp:TemplateField>
            <HeaderTemplate>
                <asp:CheckBox ID="chkboxSelectAll" runat="server" AutoPostBack="true" OnCheckedChanged="GetMobileNumberWithCheckBoxCheckUnCheck"
                    TextAlign="Left"   />
            </HeaderTemplate>
            <ItemTemplate>
                <asp:CheckBox ID="chkEmp" runat="server" AutoPostBack="true" OnCheckedChanged="GetMobileNumberWithCheckBoxCheckUnCheck">
                </asp:CheckBox>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<br />
<asp:TextBox ID="TextBox2" runat="server" TextMode="MultiLine" Width="192px"></asp:TextBox>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(int)),
                    new DataColumn("Name", typeof(string)),
                    new DataColumn("Mobile",typeof(Int64)) });
        dt.Rows.Add(1, "John Hammond", 1236547690);
        dt.Rows.Add(2, "Mudassar Khan", 6985479651);
        dt.Rows.Add(3, "Suzanne Mathews", 2315647892);
        dt.Rows.Add(4, "Robert Schidner", 6598745633);
        gvcntct.DataSource = dt;
        gvcntct.DataBind();
    }
}

protected void GetMobileNumberWithCheckBoxCheckUnCheck(object sender, EventArgs e)
{
    string controlId = (sender as CheckBox).ID;
    bool allchecked = true;
    string numbers = "";
    foreach (GridViewRow row in gvcntct.Rows)
    {
        CheckBox chkRow = (CheckBox)row.FindControl("chkEmp");
        if (controlId == "chkboxSelectAll" && (sender as CheckBox).Checked)
        {
            chkRow.Checked = true;
        }
        else if (controlId == "chkboxSelectAll" && !(sender as CheckBox).Checked)
        {
            allchecked = false;
            chkRow.Checked = false;
        }

        if (!chkRow.Checked)
        {
            allchecked = false;
        }
        else
        {
            if (!string.IsNullOrEmpty(numbers))
            {
                numbers += ",";
            }
            numbers += row.Cells[2].Text.Trim();

        }
    }
    ((CheckBox)gvcntct.HeaderRow.FindControl("chkboxSelectAll")).Checked = allchecked ? true : false;
    TextBox2.Text = numbers;
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        Dim dt As New DataTable()
        dt.Columns.AddRange(New DataColumn(2) {New DataColumn("Id", GetType(Integer)), New DataColumn("Name", GetType(String)), New DataColumn("Mobile", GetType(Int64))})
        dt.Rows.Add(1, "John Hammond", 1236547690)
        dt.Rows.Add(2, "Mudassar Khan", 6985479651L)
        dt.Rows.Add(3, "Suzanne Mathews", 2315647892UI)
        dt.Rows.Add(4, "Robert Schidner", 6598745633L)
        gvcntct.DataSource = dt
        gvcntct.DataBind()
    End If
End Sub

Protected Sub GetMobileNumberWithCheckBoxCheckUnCheck(sender As Object, e As EventArgs)
    Dim controlId As String = TryCast(sender, CheckBox).ID
    Dim allchecked As Boolean = True
    Dim numbers As String = ""
    For Each row As GridViewRow In gvcntct.Rows
        Dim chkRow As CheckBox = DirectCast(row.FindControl("chkEmp"), CheckBox)
        If controlId = "chkboxSelectAll" AndAlso TryCast(sender, CheckBox).Checked Then
            chkRow.Checked = True
        ElseIf controlId = "chkboxSelectAll" AndAlso Not TryCast(sender, CheckBox).Checked Then
            allchecked = False
            chkRow.Checked = False
        End If

        If Not chkRow.Checked Then
            allchecked = False
        Else
            If Not String.IsNullOrEmpty(numbers) Then
                numbers += ","
            End If

            numbers += row.Cells(2).Text.Trim()
        End If
    Next
    DirectCast(gvcntct.HeaderRow.FindControl("chkboxSelectAll"), CheckBox).Checked = If(allchecked, True, False)
    TextBox2.Text = numbers
End Sub

2. By calling with seperate Event for HeaderCheckBox and DataRow CheckBox.

HTML

<asp:GridView ID="gvcntct" runat="server" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="Sl. No." />
        <asp:BoundField DataField="Name" HeaderText="Contact Name" />
        <asp:BoundField DataField="Mobile" HeaderText="Mobile Number" />
        <asp:TemplateField>
            <HeaderTemplate>
                <asp:CheckBox ID="chkboxSelectAll" runat="server" AutoPostBack="true" OnCheckedChanged="chkboxSelectAll_CheckedChanged"
                    TextAlign="Left" />
            </HeaderTemplate>
            <ItemTemplate>
                <asp:CheckBox ID="chkEmp" runat="server" AutoPostBack="true" OnCheckedChanged="chkEmp_CheckedChanged">
                </asp:CheckBox>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<br />
<asp:TextBox ID="TextBox2" runat="server" TextMode="MultiLine" Width="192px"></asp:TextBox>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(int)),
                    new DataColumn("Name", typeof(string)),
                    new DataColumn("Mobile",typeof(Int64)) });
        dt.Rows.Add(1, "John Hammond", 1236547690);
        dt.Rows.Add(2, "Mudassar Khan", 6985479651);
        dt.Rows.Add(3, "Suzanne Mathews", 2315647892);
        dt.Rows.Add(4, "Robert Schidner", 6598745633);
        gvcntct.DataSource = dt;
        gvcntct.DataBind();
    }
}

protected void chkboxSelectAll_CheckedChanged(object sender, EventArgs e)
{
    string numbers = "";
    foreach (GridViewRow row in gvcntct.Rows)
    {
        CheckBox chkRow = (CheckBox)row.FindControl("chkEmp");
        if (((CheckBox)gvcntct.HeaderRow.FindControl("chkboxSelectAll")).Checked == true)
        {
            chkRow.Checked = true;
            numbers += row.Cells[2].Text.Trim() + ",";
        }
        else
        {
            chkRow.Checked = false;
        }
    }
    TextBox2.Text = numbers.Length > 0 ? numbers.Remove(numbers.Length - 1, 1) : string.Empty;
}

protected void chkEmp_CheckedChanged(object sender, EventArgs e)
{
    string numbers = "";
    bool allchecked = true;
    CheckBox chkHeader = (CheckBox)gvcntct.HeaderRow.FindControl("chkboxSelectAll");
    foreach (GridViewRow row in gvcntct.Rows)
    {
        if (!(row.FindControl("chkEmp") as CheckBox).Checked)
        {
            allchecked = false;
            break;
        }
    }
    foreach (GridViewRow row in gvcntct.Rows)
    {
        if ((row.FindControl("chkEmp") as CheckBox).Checked)
        {
            numbers += row.Cells[2].Text.Trim() + ",";
        }
    }

    chkHeader.Checked = allchecked == true ? true : false;
    TextBox2.Text = numbers.Length > 0 ? numbers.Remove(numbers.Length - 1, 1) : string.Empty;
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        Dim dt As New DataTable()
        dt.Columns.AddRange(New DataColumn(2) {New DataColumn("Id", GetType(Integer)), New DataColumn("Name", GetType(String)), New DataColumn("Mobile", GetType(Int64))})
        dt.Rows.Add(1, "John Hammond", 1236547690)
        dt.Rows.Add(2, "Mudassar Khan", 6985479651L)
        dt.Rows.Add(3, "Suzanne Mathews", 2315647892UI)
        dt.Rows.Add(4, "Robert Schidner", 6598745633L)
        gvcntct.DataSource = dt
        gvcntct.DataBind()
    End If
End Sub

Protected Sub chkboxSelectAll_CheckedChanged(sender As Object, e As EventArgs)
    Dim numbers As String = ""
    For Each row As GridViewRow In gvcntct.Rows
        Dim chkRow As CheckBox = DirectCast(row.FindControl("chkEmp"), CheckBox)
        If DirectCast(gvcntct.HeaderRow.FindControl("chkboxSelectAll"), CheckBox).Checked = True Then
            chkRow.Checked = True
            numbers += row.Cells(2).Text.Trim() + ","
        Else
            chkRow.Checked = False
        End If
    Next
    TextBox2.Text = If(numbers.Length > 0, numbers.Remove(numbers.Length - 1, 1), String.Empty)
End Sub

Protected Sub chkEmp_CheckedChanged(sender As Object, e As EventArgs)
    Dim numbers As String = ""
    Dim allchecked As Boolean = True
    Dim chkHeader As CheckBox = DirectCast(gvcntct.HeaderRow.FindControl("chkboxSelectAll"), CheckBox)
    For Each row As GridViewRow In gvcntct.Rows
        If Not TryCast(row.FindControl("chkEmp"), CheckBox).Checked Then
            allchecked = False
            Exit For
        End If
    Next
    For Each row As GridViewRow In gvcntct.Rows
        If TryCast(row.FindControl("chkEmp"), CheckBox).Checked Then
            numbers += row.Cells(2).Text.Trim() + ","
        End If
    Next

    chkHeader.Checked = If(allchecked = True, True, False)
    TextBox2.Text = If(numbers.Length > 0, numbers.Remove(numbers.Length - 1, 1), String.Empty)
End Sub

In both the cases you will get below output.