asp.net - 预期表达

Question

我收到以下代码的构建错误...

Private Property GridViewSortDirection() As String

    Get
        Return If(TryCast(ViewState("SortDirection"), String), "ASC")
    End Get
    Set(ByVal value As String)
        ViewState("SortDirection") = value
    End Set

End Property

它发生在下一行...

Return If(TryCast(ViewState("SortDirection"), String), "ASC")

错误返回...

错误11 C:\ inetpub \ wwwroot \ TPSupport \ main \ UserControls \ grid.ascx.vb(192):错误BC30201:需要表达式。

有任何想法吗

谢谢

它是C#的转换

private string GridViewSortDirection
{
   get { return ViewState["SortDirection"] as string ?? "ASC"; }
   set { ViewState["SortDirection"] = value; }
}

Answer 1

我不熟悉VB，但是使用If关键字表明您正在比较TryCast和"ASC"的结果，

通过使用类似的比较运算符来尝试这种方式

 Return If(TryCast(ViewState("SortDirection"), String) <> "ASC")