VB .NET空条件
问题描述:
这是我的代码 -VB .NET空条件
Dim provider As CultureInfo = CultureInfo.InvariantCulture
Dim a1 As DateTime = Nothing
insexp = DateTime.ParseExact(date1.SelectedValue, "MMMM yyyy", provider)
If a1.Month = Today.Month AndAlso a1.Year = Today.Year Then
a1 = Today.Date
End If
这只会工作,如果date1.selectedvalue不为空,但如果是空会崩溃。 我如何给条件来运行这只有如果不是空? 感谢
答
If date1.SelectedValue IsNot Nothing Then
...
End If
答
Dim provider As CultureInfo = CultureInfo.InvariantCulture
Dim a1 As DateTime = Nothing
If not String.IsNullOrEmpty(date1.SelectedValue) Then
insexp = DateTime.ParseExact(date1.SelectedValue, "MMMM yyyy", provider)
End If
If a1.Month = Today.Month AndAlso a1.Year = Today.Year Then
a1 = Today.Date
End If