Execute code based on Server Side Yes No Confirmation Box on Button Click using C# and VB.Net in ASP.Net

Hey micah,

Please refer below sample.

HTML

<script type="text/javascript">
    function Confirm() {
        var confirm_value = document.createElement("INPUT");
        confirm_value.type = "hidden";
        confirm_value.name = "confirm_value";
        if (confirm("Do you want to delete data?")) {
            confirm_value.value = "Yes";
        } else {
            confirm_value.value = "No";
        }
        document.forms[0].appendChild(confirm_value);
    }
</script>
<div>
    <asp:DropDownList runat="server" ID="ddlCountry">
    </asp:DropDownList>
    <asp:Button ID="btnConfirm" runat="server" OnClick="Delete" Text="Delete" OnClientClick="Confirm()" />
</div>

Namespaces

C#

using System.Data;
using System.Data.SqlClient;
using System.Configuration;

VB.Net

Imports System.Data.SqlClient
Imports System.Data

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindList();
    }
}

private void BindList()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CustomerId, Country FROM Customers", con))
        {
            using (SqlDataAdapter da = new SqlDataAdapter(cmd))
            {
                using (DataTable dt = new DataTable())
                {
                    da.Fill(dt);
                    ddlCountry.DataTextField = "Country";
                    ddlCountry.DataValueField = "CustomerId";
                    ddlCountry.DataSource = dt;
                    ddlCountry.DataBind();
                    ddlCountry.Items.Insert(0, new ListItem("--Select Items--", "0"));
                }
            }
        }
    }
}

protected void Delete(object sender, EventArgs e)
{
    string confirmValue = Request.Form["confirm_value"];

    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("DELETE FROM Customers WHERE Country = @Country", con))
        {
            cmd.Parameters.AddWithValue("@Country", ddlCountry.SelectedItem.Text);
            if (confirmValue == "Yes")
            {
                this.Page.ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('You clicked YES!')", true);
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
            else
            {
                this.Page.ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('You clicked NO!')", true);
            }
            this.BindList();
        }
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindList()
    End If
End Sub

Private Sub BindList()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT CustomerId, Country FROM Customers", con)
            Using da As SqlDataAdapter = New SqlDataAdapter(cmd)
                Using dt As DataTable = New DataTable()
                    da.Fill(dt)
                    ddlCountry.DataTextField = "Country"
                    ddlCountry.DataValueField = "CustomerId"
                    ddlCountry.DataSource = dt
                    ddlCountry.DataBind()
                    ddlCountry.Items.Insert(0, New ListItem("--Select Items--", "0"))
                End Using
            End Using
        End Using
    End Using
End Sub

Protected Sub Delete(ByVal sender As Object, ByVal e As EventArgs)
    Dim confirmValue As String = Request.Form("confirm_value")
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString

    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("DELETE FROM Customers WHERE Country = @Country", con)
            cmd.Parameters.AddWithValue("@Country", ddlCountry.SelectedItem.Text)
            If confirmValue = "Yes" Then
                Me.Page.ClientScript.RegisterStartupScript(Me.GetType(), "alert", "alert('You clicked YES!')", True)
                con.Open()
                cmd.ExecuteNonQuery()
                con.Close()
            Else
                Me.Page.ClientScript.RegisterStartupScript(Me.GetType(), "alert", "alert('You clicked NO!')", True)
            End If
            Me.BindList()
        End Using
    End Using
End Sub

Screenshot