Disable OnClientClick event from code behind using C# and VB.Net in ASP.Net

Hi fkz2899,

Refer below sample.

HTML

<asp:GridView ID="GridView1" CssClass="Grid" runat="server" OnRowDeleting="GridView1_OnRowDeleting"
    AutoGenerateColumns="false" OnRowDataBound="OnRowDataBound">
    <Columns>
        <asp:BoundField DataField="Item" HeaderText="Item" />
        <asp:BoundField DataField="Price" HeaderText="Price" />
        <asp:CommandField ShowDeleteButton="True" ButtonType="Button" />
    </Columns>
</asp:GridView>
<div style="text-align: center; width: 250px; margin-bottom: 10px">
    <b>
        <asp:Button ID="dd" class="btn btn-warning" Style="text-align: center; margin-left: 100%"
            runat="server" OnClick="dd_Click" OnClientClick="return confirm('Are you sure you want to Place Order?');"
            Text="Place Order" /></b></div>

Namespaces

C#

using System.Data;

VB.Net

Imports System.Data

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[2] { new DataColumn("Item"), new DataColumn("Price") });
        dt.Rows.Add("Shirt", 450);
        dt.Rows.Add("Jeans", 3200);
        dt.Rows.Add("Trousers", 1900);
        Session["buy"] = dt;
        BindGrid();
    }
}

protected void BindGrid()
{
    GridView1.DataSource = Session["buy"] as DataTable;
    GridView1.DataBind();
}

protected void GridView1_OnRowDeleting(object sender, GridViewDeleteEventArgs e)
{
    DataTable dt = new DataTable();
    dt = (DataTable)Session["buy"];
    dt.Rows[e.RowIndex].Delete();
    dt.AcceptChanges();
    if (dt.Rows.Count == 0)
    {
        dd.OnClientClick = null;
    }
    GridView1.DataSource = dt;
    GridView1.DataBind();
}

protected void OnRowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        string item = e.Row.Cells[0].Text;
        foreach (Button button in e.Row.Cells[2].Controls.OfType<Button>())
        {
            if (button.CommandName == "Delete")
            {
                button.Attributes["onclick"] = "if(!confirm('Do you want to delete " + item + "?')){ return false; };";
            }
        }
    }
}

protected void dd_Click(object sender, EventArgs e)
{

}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim dt As DataTable = New DataTable()
        dt.Columns.AddRange(New DataColumn(1) {New DataColumn("Item"), New DataColumn("Price")})
        dt.Rows.Add("Shirt", 450)
        dt.Rows.Add("Jeans", 3200)
        dt.Rows.Add("Trousers", 1900)
        Session("buy") = dt
        BindGrid()
    End If
End Sub

Protected Sub BindGrid()
    GridView1.DataSource = TryCast(Session("buy"), DataTable)
    GridView1.DataBind()
End Sub

Protected Sub GridView1_OnRowDeleting(ByVal sender As Object, ByVal e As GridViewDeleteEventArgs)
    Dim dt As DataTable = New DataTable()
    dt = CType(Session("buy"), DataTable)
    dt.Rows(e.RowIndex).Delete()
    dt.AcceptChanges()

    If dt.Rows.Count = 0 Then
        dd.OnClientClick = Nothing
    End If

    GridView1.DataSource = dt
    GridView1.DataBind()
End Sub

Protected Sub OnRowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DataRow Then
        Dim item As String = e.Row.Cells(0).Text
        For Each button As Button In e.Row.Cells(2).Controls.OfType(Of Button)()
            If button.CommandName = "Delete" Then
                button.Attributes("onclick") = "if(!confirm('Do you want to delete " & item & "?')){ return false; };"
            End If
        Next
    End If
End Sub

Protected Sub dd_Click(ByVal sender As Object, ByVal e As EventArgs)
End Sub