Question

vb中从键盘输入一个字符串（要求任意长度），然后删除其中的非数字字符，最后输出。(FOR语句)

Answer 1

Private Sub Text1_KeyPress(KeyAscii As Integer)
If KeyAscii = vbKeyReturn Then
Dim Txt As String
For i = 1 To Len(Text1.Text)
If Asc(Mid(Text1.Text, i, 1)) >= 48 And Asc(Mid(Text1.Text, i, 1)) <= 57 Then Txt = Txt & Mid(Text1.Text, i, 1)
Next i
MsgBox Txt
End If
End Sub

另外：
If Asc(Mid(Text1.Text, i, 1)) >= 48 And Asc(Mid(Text1.Text, i, 1)) <= 57 Then Txt = Txt & Mid(Text1.Text, i, 1) 还可以简化为：
If Mid(Text1.Text, i, 1) Like "[0-9]" Then Txt = Txt & Mid(Text1.Text, i, 1)