Question

我想出了如何清除文本框，但是当我在MessageBox上按 No 时它会清除。我希望它清除用户是否选择是。如果用户选择否，那么我想什么都不做。

    Private Sub BtnFah_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnFah.Click
        Try
            Dim intFah As Integer
            intFah = CInt(TxtBoxTemp.Text)
            intFah = (intFah * 9) / 5 - 32
            If MessageBox.Show(intFah.ToString & ControlChars.CrLf & "Would you like to start another temp conversion?", "Result", MessageBoxButtons.YesNo) Then
                TxtBoxTemp.Text = String.Empty
            End If
        Catch
            MessageBox.Show("Would you like to start another temp conversion?", "System Error", MessageBoxButtons.YesNo)

        End Try
    End Sub

Answer 1

您需要比较DialogResult

 Public Class Form1    
    Private Sub BtnFah_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnFah.Click
        Try
            Dim intFah As Integer
            intFah = CInt(TxtBoxTemp.Text)
            intFah = (intFah * 9) / 5 - 32
            If MessageBox.Show(intFah.ToString & ControlChars.CrLf & "Would you like to start another temp conversion?", "Result", MessageBoxButtons.YesNo) = DialogResult.Yes Then
                TxtBoxTemp.Text = String.Empty
            End If
        Catch
            MessageBox.Show("Would you like to start another temp conversion?", "System Error", MessageBoxButtons.YesNo)

        End Try
    End Sub
End Class

Answer 2

MessageBox.Show返回DialogResult。您应该检查DialogResult.Yes：

If MessageBox.Show(...) = DialogResult.Yes Then
   TxtBoxTemp.Text = String.Empty
End If

Answer 3

使用Q作为变量并且暗淡如msgboxresult使msgbox有结果，如果按yes，文本框将清除，如果没有，则它将返回或什么都不做

 Dim q As MsgBoxResult
            q = MsgBox("Your Question", vbYesNo)
            If q = vbYes Then
                TextBox1.Clear()
            Else
                Return
            End If

Answer 4

试试这个......

If MessageBox.Show("Your Message", "Title", MessageBoxButtons.YesNo) = DialogResult.Yes Then
textbox.clear()
End If

使用MessageBox yes按钮清除TextBox

4 个答案: