将 TextBox 的 NAME 输入到 TextBox 中，然后就可以检索命名的 TextBox 的内容

Question

for example, I want to declare the textbox based on what I write in the box. if I write textbox1. if I type textbox2.text then it will be textbox2.text

Dim txt As TextBox = TextBox2.Text.ToString
Dim txt As String = TextBox2.Text

none of the methods is valid

Answer 1

Your verbiage, although confusing, makes it seem like you want to type the NAME of a TextBox into a TextBox and then be able to retrieve the contents of the named TextBox. If that's correct, you're probably looking for Controls.Find() with the recurse option:

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Dim txtBoxName As String = TextBox1.Text.Trim
    If txtBoxName.Length > 0 Then
        Dim ctl As Control = Me.Controls.Find(txtBoxName, True).FirstOrDefault
        If Not IsNothing(ctl) AndAlso TypeOf (ctl) Is TextBox Then
            Dim tb As TextBox = DirectCast(ctl, TextBox)
            ' ... do something with "tb" ...
            Dim value As String = tb.Text
            MessageBox.Show(value)
        Else
            MessageBox.Show("Control not found, or incorrect type!")
        End If
    End If
End Sub