Msgbox Yes No & 在 VB.NET 2010 中工作的取消按钮

Question

Below is my code for a MsgBox. The Yes button is working, but when I click No or Cancel it still deletes the data...

        strup = "DELETE FROM student WHERE urno =" & CInt(txtUrn.Text) & ";"
        Dim command As New OleDb.OleDbCommand(strup, con)
        MsgBox("Do you want to delete record(s)", MsgBoxStyle.YesNoCancel, "Confirm Delete")
        command.ExecuteNonQuery()
        con.Close()

How do I have it cancel the delete operation when clicking No or Cancel ?

Answer 1

Use the basic If statement to check the return value of MsgBox . The MsgBox doesn't cancel anything by itself.

If MsgBox("Prompt", MsgBoxStyle.YesNoCancel, "Title") = MsgBoxResult.Yes Then
    ' execute command
End If

You could also use MsgBoxStyle.YesNo to get only the Yes and No buttons.

Answer 2

Similar to If...Then , but I think this is cleaner

Select Case MsgBox("Are you sure ?", MsgBoxStyle.YesNo, "Delete")
    Case MsgBoxResult.Yes
        ' Do something if yes
    Case MsgBoxResult.No
        ' Do something if no
End Select

Answer 3

        If MsgBox("Are you sure ?", MsgBoxStyle.YesNo, "Delete") = MsgBoxResult.Yes Then
            strup = "DELETE FROM student WHERE urno =" & CInt(txtUrn.Text) & ";"
            Dim command As New OleDb.OleDbCommand(strup, con)
            'MsgBox("Do you want to delete record(s)", MsgBoxStyle.YesNoCancel, "Confirm Delete")
            command.ExecuteNonQuery()
            con.Close()
            txtUrn.Text = ""
            txt10Per.Text = ""
            txt12Per.Text = ""
            txtCAdd.Text = ""
            txtEid.Text = ""
            txtFname.Text = ""
            txtGPer.Text = ""
            txtMno.Text = ""
            txtName.Text = ""
            txtPAdd.Text = ""
            cmb10YofPass.Text = ""
            cmb12YofPass.Text = ""
            cmbDate.Text = ""
            cmbGender.Text = ""
            cmbMonth.Text = ""
            cmbNameofGCourse.Text = ""
            cmbYear.Text = ""
            ComboBox1.Text = ""
            TextBox1.Text = ""
            MsgBox("Record Deleted Successfully")
        ElseIf MsgBoxResult.No Then

        End If

Answer 4

MsgBox 仍然不能在 ASP.NET 生产环境或 QA 而不是开发环境中工作。