有一点点资料:http://bbs.aspx.cn/dotnetbbs/Showtopic.aspx?Forum_ID=5&Id=36871
If TextBox1.Text = "" Then
MessageBox.Show("You must enter a name.", "Name Entry Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
Else
' Code to act on the data entered would go here.
End If
转载于:https://www.cnblogs.com/LCX/archive/2004/09/19/44638.html