在vb.net中使用Eval

Question

hiii everyone....

i have small problem with my code in vb.net that i want to use (Eval) in my project

so i write this code :

<asp:Label ID="Label1" runat="server"
 Text='<%#Eval("PAG_PAGES") == null ? "" : ((PostAgenciesModel.PAG_PAGES)(Eval("PAG_PAGES"))).PAGE_TITLE_AR %>' />

and this code i used in my C# project .... all want to show the (Label1) in inside my GridView....

("PAG_PAGES") is the name of table..

PostAgenciesModel is the edmx ...

PAGE_TITLE_AR is the colum in ("PAG_PAGES") that i want to show it

can anyone help plzzz

thanxx

Answer 1

The issue is that you are using C# features in a VB.NET web application.

The null keyword and the ?: and == operators are C# constructs

In VB.NET, null is Nothing , == is IS and ?: is the IIf function.

Answer 2

<%# If(Eval("PAG_PAGES") Is Nothing, 
        "", 
        DirectCast(Eval("PAG_PAGES"), PostAgenciesModel.PAG_PAGES).PAGE_TITLE_AR) %>

Elaborating on what Oded wrote:

expr == null  --->  expr Is Nothing
a ? b : c     --->  If(a, b, c)
(Type)expr    --->  DirectCast(expr, Type)