Question

Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click
    If RaiseEvent Button1.Click = True Then
        Dim result As Integer
        Dim Fnum As Integer = TextBox1.Text
        Dim Snum As Integer = TextBox2.Text
        result = Fnum + Snum
        Label1.Text = result

你好，我这个代码有问题。我试图让它说按下按钮，它激活这个其他按钮的方法。我在RaiseEvent部分收到错误。它在R上放了一条曲线，并说“预期的表达。抱歉我对VB有点新，需要一点帮助。谢谢

Answer 1

RaiseEvent用于引发事件，而不是查明事件是否已被引发。

根据您在其他帖子中的评论，您可能需要保留一个标记，以便在点击操作员按钮时进行跟踪。

像这样，

Dim OperatorClicked As Boolean

Private Sub OperatorButton_Click(sender As Object, e As EventArgs) Handles Button1.Click, Button2.Click, Button3.Click, Button4.Click
    OperatorClicked = True
End Sub

Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click
    If OperatorClicked Then
        Dim result As Integer
        Dim Fnum As Integer = TextBox1.Text
        Dim Snum As Integer = TextBox2.Text
        result = Fnum + Snum '-- you need to modify this too to specify correct operator
        Label1.Text = result
    End If
    OperatorClicked = False
End Sub

修改

我们不使用布尔标志来跟踪是否单击了运算符，而是使用字符串来跟踪单击的运算符。这里我假设按钮Text分别有+， - ，/，*。（但理想的方法是使用Tag属性。这将帮助您保持显示文本与代码不相关。）

Dim OperatorClicked As String Private Sub OperatorButton_Click(sender As Object, e As EventArgs) Handles Button1.Click, Button2.Click, Button3.Click, Button4.Click OperatorClicked = CType(sender, Button).Text.Trim End Sub Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click If OperatorClicked <> "" Then Dim result As Integer Dim Fnum As Integer = TextBox1.Text Dim Snum As Integer = TextBox2.Text Select Case OperatorClicked Case "+" result = Fnum + Snum Case "-" result = Fnum - Snum '-- similarly other cases End Select Label1.Text = result End If OperatorClicked = "" End Sub

提升事件后的预期表达

1 个答案: