using values within if conditions in mark up

Question

I want to use a value that is pulled from the SQL within the if statement. Ideally i want to do the equivalent of

<% If DataBinder.Eval(Container, "DataItem.BookID") == 1 Then%>

Is there a way to do this with the correct syntax?

DataBinder.Eval(Container, "DataItem.BookID") throws an error as Container is not declared. however the value of BookID is the value i need to compare to 1. — Sophie, Jun 20 '12 at 10:57

Ebad Masood · Answer 1 · 2012-06-20T11:34:46.823

2

This is how you put conditions in aspx file. Just a rough sample base on what I understand:

<%# System.Convert.ToInt32((DataBinder.Eval(Container.DataItem, "BookID")!="") ? DataBinder.Eval(Container.DataItem, "BookID"):0) %>

Make sure you have int in BookID not any other type.

Explaining Further:

In case you want to have an if else condition:

<%# If DataBinder.Eval(Container.DataItem, "DATAFIELD") <> "" Then

   Response.Write("something")

End If %> // This is invalid

The above statement can be properly written in aspx file as this:

<%# DataBinder.Eval(Container.DataItem, "DataField").Equals("")?"":"Something"%>

edited Jun 20 '12 at 11:34

answered Jun 20 '12 at 10:59

Ebad Masood

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How can i get the value from that into an if statement? – Sophie Jun 20 '12 at 11:13
This does not work for if bookid = 1 then use this Hyperlink else use this hyperlink – Sophie Jun 20 '12 at 11:51
<% If "ParentTypeID" = 1 Then%> <% Else%> <%End If%> that is what i want to do, it is getting the value of ParentTypeID that i am struggling with – Sophie Jun 20 '12 at 11:57
both condition doing the same thing? – Ebad Masood Jun 20 '12 at 12:02
what would i put into the "something"? i dont understand how that works – Sophie Jun 20 '12 at 12:10
You can get it like this: <% If <%# Convert.ToInt32(Eval("ParentTypeID")) == 1 Then%>, still pretty difficult to understand your logic. – Ebad Masood Jun 20 '12 at 12:13
instead of "something" you put *else* condition, whatever that is. – Ebad Masood Jun 20 '12 at 12:16
your comment with the if does not work there are too starting tags – Sophie Jun 20 '12 at 12:19
try this: <% If Convert.ToInt32(Eval("ParentTypeID")) == 1 Then%> – Ebad Masood Jun 20 '12 at 12:23
that doesnt work with the same exception i was getting before – Sophie Jun 20 '12 at 12:52

score 0 · Answer 2 · answered Jun 29 '12 at 02:22

I'm not sure if this can be done or not the way you are requesting it.

As you may or may not know, the typical way to do this is to have a control in your markup, like so

<asp:listView ID="SophiesListView" ...
..
<ItemTemplate>
<asp:HyperLink ID="hlGlossary" title="click here for more information" target="_blank" runat="server" />
</ItemTemplate>
</asp:listView />

Then, in the codebehind, find your listview / repeater / datagrid or what have you and choose ItemDataBound. Inside this event, do something like this:

If e.Item.DataItem("vehicleType") IsNot DBNull.Value AndAlso e.Item.DataItem("vehicleType") = "JETSKI" Then
    DirectCast(e.Item.FindControl("hlGlossary"), HyperLink).NavigateUrl = "Glossary.aspx#JETSKI"
    DirectCast(e.Item.FindControl("hlGlossary"), HyperLink).Text = "?"
End If

score -1 · Answer 3 · answered Jun 20 '12 at 13:05

To keep your page logic as simple as possible your best bet is to data bind to the Visible property of controls. For example, if you want to only show some html if the BookID == 1 then create a new property on your data source like this

public bool Show
{
     get
     {
         return BookID == 1;
     }
}

and in your page you'd have

<asp:Placeholder runat="server" Visible='<%# Eval("Show") %>'>
    ...html goes here...
</asp:Placeholder>

using values within if conditions in mark up

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