不宴烂知道你说的空是哪种意思?有两种说法,一种是String.Empty,例如Dim s As String = String.Empty 等雀茄同于 Dim s As String = ""这种情晌岁漏况下直接If s = "" Then就可以判断是不是空.还有一种是Nothing,必须要用If IsNothing(s) Then来判断.