Using '<%# Eval("item") %>'; Handling Null Value and showing 0 against - asp.net

Question

If dataitem is Null I want to show 0
<asp:Label ID="Label18" Text='<%# Eval("item") %>' runat="server"></asp:Label>
How can I accomplish this?

Answer 1

You can also create a public method on the page then call that from the code-in-front.
e.g. if using C#:
public string ProcessMyDataItem(object myValue)
{
if (myValue == null)
{
return "0 value";
}
return myValue.ToString();
}
Then the label in the code-in-front will be something like:
<asp:Label ID="Label18" Text='<%# ProcessMyDataItem(Eval("item")) %>' runat="server"></asp:Label>
Sorry, haven't tested this code so can't guarantee I got the syntax of "<%# ProcessMyDataItem(Eval("item")) %>" entirely correct.

Answer 2

I'm using this for string values:
<%#(String.IsNullOrEmpty(Eval("Data").ToString()) ? "0" : Eval("Data"))%>
You can also use following for nullable values:
<%#(Eval("Data") == null ? "0" : Eval("Data"))%>
Also if you're using .net 4.5 and above I suggest you use strongly typed data binding:
<asp:Repeater runat="server" DataSourceID="odsUsers" ItemType="Entity.User">
<ItemTemplate>
<%# Item.Title %>
</ItemTemplate>
</asp:Repeater>

Answer 3

I use the following for VB.Net:
<%# If(Eval("item").ToString() Is DBNull.Value, "0 value", Eval("item")) %>

Answer 4

It should work as well
Eval("item") == null?"0": Eval("item");

Answer 5

Moreover, you can use (x = Eval("item") ?? 0) in this case.
http://msdn.microsoft.com/en-us/library/ms173224.aspx

Answer 6

I don't know ASP.NET very well, but can you use the ternary operator?
http://en.wikipedia.org/wiki/Ternary_operation
Something like:
(x=Eval("item")) == Null ? 0 : x

Answer 7

Use IIF.
<asp:Label ID="Label18" Text='<%# IIF(Eval("item") Is DBNull.Value,"0", Eval("item") %>'
runat="server"></asp:Label>

Answer 8

try this code it might be useful -
<%# ((DataBinder.Eval(Container.DataItem,"ImageFilename").ToString()=="") ? "" :"<a
href="+DataBinder.Eval(Container.DataItem, "link")+"><img
src='/Images/Products/"+DataBinder.Eval(Container.DataItem,
"ImageFilename")+"' border='0' /></a>")%>

Answer 9

Used a modified version of Jason's answer:
public string ProcessMyDataItem(object myValue)
{
if (myValue.ToString().Length < 1)
{
return "0 value";
}
return myValue.ToString();
}

Answer 10

Try replacing <%# Eval("item") %> with <%# If(Eval("item"), "0 value") %> (or <%# Eval("item") ?? "0 value" %>, when using C#).

Answer 11

I have tried this code and it works well for both null and empty situations :
'<%# (Eval("item")=="" || Eval("item")==null) ? "0" : Eval("item")%>'

Answer 12

You can use the following for VB.net, especially if the value is a boolean:
<%# IIf(Eval("mydata").Equals(DBNull.Value), 0, Eval("mydata"))%>
For example, use this to automatically check or uncheck a checkbox with inline IIF eval:
<asp:CheckBox ID="mycheckbox" runat="server" Checked='<%# IIf(Eval("mydata").Equals(DBNull.Value), 0, Eval("mydata"))%>' />
The other method with .ToString will cause an error trying to convert the DBnull to a boolean.