Question

Public Class Form1
Public digits As String = "0123456789"
Public userInput As String
Public digitCount As Integer = 0

Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
    userInput = TextBox1.Text
End Sub

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    digitCount = userInput.Count(Function(c) Char.IsDigit(c))


End Sub

Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click

End Sub


Private Sub MaskedTextBox1_MaskInputRejected(sender As Object, e As MaskInputRejectedEventArgs) Handles MaskedTextBox1.MaskInputRejected
    MaskedTextBox1.Text = digitCount.ToString
End Sub

我运行这个程序。我在textbox1中输入带有数字的字符串。单击Button1。 MaskedTextBox1中没有任何内容。有任何想法吗？我不知所措。在我的知识中，我尝试了一切。

Answer 1

在您的Button1.Click事件处理程序中，您实际上并没有告诉它做任何事情来设置MaskedTextBox的值。您似乎放在MaskedTextBox1.MaskInputRejected处理程序中的那行代码。尝试重构代码，如下所示：

Public Class Form1
    Public digits As String = "0123456789"
    Public userInput As String
    Public digitCount As Integer = 0

    Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
        userInput = TextBox1.Text
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        digitCount = userInput.Count(Function(c) Char.IsDigit(c))

        MaskedTextBox1.Text = digitCount.ToString
    End Sub

    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click

    End Sub


    Private Sub MaskedTextBox1_MaskInputRejected(sender As Object, e As MaskInputRejectedEventArgs) Handles MaskedTextBox1.MaskInputRejected

    End Sub

Answer 2

问题在于您没有将数字计数逻辑的输出分配给蒙版文本框，如下所示：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    MaskedTextBox1.Text = userInput.Count(Function(c) Char.IsDigit(c)).ToString()
End Sub

VB.NET GUI - 按钮单击不执行任务

2 个答案: