Call RowDeleting event on Button Click outside GridView using C# and VB.Net in ASP.Net

Hi akhter,

I have created a sample please take its reference and correct your code.

HTML

<asp:GridView runat="server" ID="gvCustomers" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="CustomerID" HeaderText="ID" />
        <asp:BoundField DataField="Name" HeaderText="Name" />
        <asp:BoundField DataField="Country" HeaderText="Country" />
    </Columns>
</asp:GridView><br /><br />
<asp:Button Text="Delete All Row" runat="server" ID="btnDelete" OnClick="DeleteGridviewRow" />

Namespaces

C#

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

VB.Net

Imports System.Configuration
Imports System.Data
Imports System.Data.SqlClient

Code

C#

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

private void BindCustomer()
{
    using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conString"].ConnectionString))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CustomerID,Name,Country FROM Customers", con))
        {
            cmd.CommandType = CommandType.Text;
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                sda.SelectCommand = cmd;
                DataTable dt = new DataTable();
                sda.Fill(dt);
                this.gvCustomers.DataSource = dt;
                this.gvCustomers.DataBind();
            }
        }
    }
}

protected void DeleteGridviewRow(object sender, EventArgs e)
{
    foreach (GridViewRow row in gvCustomers.Rows)
    {
        int id = Convert.ToInt32(row.Cells[0].Text);
        using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["conString"].ConnectionString))
        {
            using (SqlCommand cmd = new SqlCommand("DELETE FROM Customers WHERE CustomerId=@CustomerId", con))
            {
                cmd.Parameters.AddWithValue("@CustomerId", id);
                cmd.CommandType = CommandType.Text;
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
}

VB.Net

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

Private Sub BindCustomer()
    Using con As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("conString").ConnectionString)
        Using cmd As SqlCommand = New SqlCommand("SELECT CustomerID,Name,Country FROM Customers", con)
            cmd.CommandType = CommandType.Text
            Using sda As SqlDataAdapter = New SqlDataAdapter()
                sda.SelectCommand = cmd
                Dim dt As DataTable = New DataTable()
                sda.Fill(dt)
                Me.gvCustomers.DataSource = dt
                Me.gvCustomers.DataBind()
            End Using
        End Using
    End Using
End Sub

Protected Sub DeleteGridviewRow(ByVal sender As Object, ByVal e As EventArgs)
    For Each row As GridViewRow In gvCustomers.Rows
        Dim id As Integer = Convert.ToInt32(row.Cells(0).Text)
        Using con As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("conString").ConnectionString)
            Using cmd As SqlCommand = New SqlCommand("DELETE FROM Customers WHERE CustomerId=@CustomerId", con)
                cmd.Parameters.AddWithValue("@CustomerId", id)
                cmd.CommandType = CommandType.Text
                con.Open()
                cmd.ExecuteNonQuery()
                con.Close()
            End Using
        End Using
    Next
End Sub