vb.net 判断inputbox中输入信息

Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim str As String
str = InputBox("123")

If Len(str) > 0 Then
'有输入并确定
MessageBox.Show(str)
Else
'无输入或取消
MessageBox.Show("no")
End If
End Sub
End Class