Question

I am trying to delete records from my table but unable to do so. I have window form with Insert, Update, Delete and Save button. I can insert data but I can’t delete specific or any records from that table. Below is my code.

Whenever I click ‘delete’ button I get (“Error while deleting record on table…” & ex.Message, “Delete Records”) msgbox only.

Am I missing something? Please advise. Any help would be great. Thank you!

Private Sub Deletebtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Deletebtn.Click

    Dim con As New SqlConnection
    Dim cmd As New SqlCommand
    Try
        con.ConnectionString = "Server=USRAG-L-0067215\SQLEXPRESS;Database=Alamo Products_Design Data;Trusted_Connection=True"
        con.Open()
        cmd.Connection = con
        cmd.CommandText = "Delete From Design_Parameters where DesignID= ? "
        cmd.ExecuteNonQuery()
        If MessageBox.Show("Do you really want to Delete this Record?", "Delete", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) = DialogResult.No Then

            MsgBox("Operation Cancelled")

            Exit Sub

        End If
    Catch ex As Exception
        MessageBox.Show("Error while deleting record on table..." & ex.Message, "Delete Records")

    Finally

        con.Close()
    End Try
End Sub

End Class

Answer 1

you need to add parameter for DesignID

Dim con As New SqlConnection
    Dim cmd As New SqlCommand
    Try
        con.ConnectionString = "Server=USRAG-L-0067215\SQLEXPRESS;Database=Alamo Products_Design Data;Trusted_Connection=True"
        con.Open()
        cmd.Connection = con
        cmd.CommandText = "Delete From Design_Parameters where DesignID= @DesignID"
    cmd.Parameters.Add(New SqlParameter("@DesignID", yourvaluehere))
        cmd.ExecuteNonQuery()
        If MessageBox.Show("Do you really want to Delete this Record?", "Delete", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) = DialogResult.No Then

            MsgBox("Operation Cancelled")

            Exit Sub

        End If
    Catch ex As Exception
        MessageBox.Show("Error while deleting record on table..." & ex.Message, "Delete Records")

    Finally

        con.Close()
    End Try