protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindGrid();
    }
}
 
private void BindGrid()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CustomerId, Name, Country FROM Customers"))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                using (DataTable dt = new DataTable())
                {
                    sda.Fill(dt);
                    GridView1.DataSource = dt;
                    GridView1.DataBind();
                }
            }
        }
    }
}

کد VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindGrid()
    End If
End Sub
 
Private Sub BindGrid()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand("SELECT CustomerId, Name, Country FROM Customers")
            Using sda As New SqlDataAdapter()
                cmd.Connection = con
                sda.SelectCommand = cmd
                Using dt As New DataTable()
                    sda.Fill(dt)
                    GridView1.DataSource = dt
                    GridView1.DataBind()
                End Using
            End Using
        End Using
    End Using
End Sub

حذف رکوردهای GridView

وقتی که بر روی دکمه Delete (حذف)کلیک میکنیم رویداد OnRowDeleting فراخوانی می شود. Customerld یک کلید اصلی است که از خصوصیت DataKey گرفته میشود و با استفاده از Customerld رکورد از جدول بانک اطلاعاتی حذف میشود.

کد #C

protected void OnRowDeleting(object sender, GridViewDeleteEventArgs e)
{
    int customerId = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0]);
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("DELETE FROM Customers WHERE CustomerId = @CustomerId"))
        {
            cmd.Parameters.AddWithValue("@CustomerId", customerId);
            cmd.Connection = con;
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }
    this.BindGrid();
}

کد VB.Net :

Protected Sub OnRowDeleting(sender As Object, e As GridViewDeleteEventArgs)
    Dim customerId As Integer = Convert.ToInt32(GridView1.DataKeys(e.RowIndex).Values(0))
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand("DELETE FROM Customers WHERE CustomerId = @CustomerId")
            cmd.Parameters.AddWithValue("@CustomerId", customerId)
            cmd.Connection = con
            con.Open()
            cmd.ExecuteNonQuery()
            con.Close()
        End Using
    End Using
    Me.BindGrid()
End Sub

برای تعیین دکمه حذف برای اولین بار از رویداد OnRowDataBound استفاده می کنیم که از جاوا اسکریپ Confirm برای زمانی که کاربر می خواهد رویداد کلیک را انجام دهد ، استفاده می کنیم.

کد #C

protected void OnRowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow && e.Row.RowIndex != GridView1.EditIndex)
    {
        (e.Row.Cells[0].Controls[0] as LinkButton).Attributes["onclick"] = "return confirm('Do you want to delete this row?');";
    }
}

 کد VB.Net

Protected Sub OnRowDataBound(sender As Object, e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DataRow AndAlso e.Row.RowIndex <> GridView1.EditIndex Then
        TryCast(e.Row.Cells(0).Controls(0), LinkButton).Attributes("onclick") = "return confirm('Do you want to delete this row?');"
    End If
End Sub

نمایش پیغام تایید بعد از کلیک کردن دکمه حذف :