IF…else with Eval is not supported+GridView+ASP.NET

Yesterday i was struggling with GridView I need to check some if..else logic and based on it have to show values in Grid..I am checking it in Eval if else but can’t get succeeded because if..else is not supprted with Eval..then how i have achieved it..its concept of “Binding Grid with functions”. Let us see..

Problem:

On binding of Grid i want to check that if entityCount>1 then have to show that value in grid with HyperLink which points to some page else show Plain Text in grid..

I was trying this one[Which won't work]

<asp:TemplateField HeaderText=”Def Price”>
<ItemTemplate>
<%# if Eval(“entityPriceCountField”) > 1%>
<asp:HyperLink ID=”lnkentityPrice” Text=’<%# Eval(“entityPriceField”) %>’ runat=”Server”   Target=”_blank” NavigateUrl=”#”/>
<%# else  %>
<asp:Label ID=”lblentityPrice” Text=’<%# Eval(“entityPriceField”) %>’ CssClass=”SearchBookingsLabelStyle” runat=”Server” />                                 
</ItemTemplate>
</asp:TemplateField>

NOTE: You can’t write like this.

Solution:

I had its solution:

1. Binded my grid with function in my .aspx.cs file.

this function check count if count>1 then text will be in hyper link else show plain text.

2.  Called it witin my Grid.

Here it is:

.aspx page 

<asp:TemplateField HeaderText=”Def Price”>
<ItemTemplate>
<asp:Label ID=”entityPrice” Text=’<%# GetEntityPriceText((double)Eval(“entityPriceField”),(int)Eval(“entityPriceCountField”))%>’ CssClass=”SearchBookingsLabelStyle” runat=”Server” />
</ItemTemplate>
</asp:TemplateField>

 .aspx.cs code

 protected string GetEntityPriceText(Nullable<double> entityprice,Nullable<int> entityPriceCount)
{
//If count>1 then show text in HyperLink
string labelText = string.Empty;
if (entityPriceCount > 1)
labelText = “<a href=MyPage.aspx’>” + entityprice.ToString() + “</a>”;
else
labelText = entityprice.ToString();
return labelText;
}

It worked like a chram!!!

CS1502+Eval+GridView+invalid arguments

Yesterday was binding my grid with function.. But it is showing me some errors which is as under

Server Error in ‘/DevelopmentWebsite’ Application.
——————————————————————————–

Compilation Error
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: CS1502: The best overloaded method match for ‘SellBooking_EventSearch.GetEntityPriceText(double?, int?)’ has some invalid arguments

Source Error:

Line 133:
Line 134:
Line 135:                                       <asp:Label ID=”entityPrice” Text=’<%# GetEntityPriceText(Eval(“entityPriceField”),Eval(“entityPriceCountField”))%>’ CssClass=”SearchBookingsLabelStyle” runat=”Server” />          

ASP.NET FUNCTION:

protected string GetEntityPriceText(Nullable<double> entityprice,Nullable<int> entityPriceCount)
{
//If count>1 then show text in HyperLink
string labelText = string.Empty;
if (entityPriceCount > 1)
//To-DO Change it to appropriate ASP Page
labelText = “<a href=’Booker.aspx’>” + entityprice.ToString() + “</a>”;
else
labelText = entityprice.ToString();
return labelText;
}

Solution and Cause of Error:

Cause of Error: Eval function returns object and my function expects double/int so it throws invalid arguments.

So just need to cast my Evals to appropriate type for my example double/int..so now it looks like this:

<asp:Label ID=”entityPrice” Text=’<%# GetEntityPriceText((double)Eval(“entityPriceField”),(int)Eval(“entityPriceCountField”))%>’ CssClass=”SearchBookingsLabelStyle” runat=”Server” />      

It ran like a charm.

Hope it will help…