Unable to use extension method within partial view

Question

I am trying to use a string extension method in a partial view. I get the following error:

'string' does not contain a definition for 'TruncateAtCharacter'

Here is the extension method:

namespace PCCMS.Core.Libraries {
    public static class Extensions {
        public static string TruncateAtCharacter(this string input, int length) {
            if (String.IsNullOrEmpty(input) || input.Length < length)
                return input;

            return string.Format("{0}...", input.Substring(0, length).Trim());
        }
    }
}

According to this previous question I need to add the namespace to web.config, however I have done this and I still receive the same error message. What's odd though, is that I do get intellisense for the extension method?

<system.web.webPages.razor>
    <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    <pages pageBaseType="PCCMS.Core.Libraries.ClientWebViewPage">
        <namespaces>
            <add namespace="System.Web.Mvc" />
            <!-- Other namespaces... -->
            <add namespace="PCCMS.Core.Libraries" />
        </namespaces>
    </pages>
</system.web.webPages.razor>

Can anyone explain why this is?

Thanks

Rob Kent · Accepted Answer · 2012-07-17T15:04:11.443

1

This should work if the namespace declaration is in the system.web.webPages.razor/namespaces element of your root Views directory web.config. If that fails, try using an explicit @using statement at the top of the View without any web.config statements. It 'should' work.

PS Is that ReSharper intellisense or VS? ReSharper explicitly tells me that an @using is required if the web.config entry is not in scope.

edited Jul 17 '12 at 15:04

answered Jul 17 '12 at 14:37

Rob Kent

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Sorry, I should have mentioned I tried adding an @using in the partial and that did not work. Neither has adding the namespace declaration to the web.config within the area, nor the one in the project root. – Rory McCrossan Jul 17 '12 at 14:54
I just copied your code and it only works if I use an @using statement in the view. Just referencing the namespace in either configs doesn't do anything. – Rob Kent Jul 17 '12 at 14:57
Okay. I just got it to work only using the web.config in the Views directory and with no @using statement in the View itself. I am using the system.web.webPages.razor/namespaces element. I didn't have that element in my root config and when I added the statement to the default system.web.pages as well, it confused the parser. Just try putting it in the Views web.config. – Rob Kent Jul 17 '12 at 15:01
1

@RoryMcCrossan, when you say the *project root* do you mean `~/web.config` or `~/Views/web.config`? Because you have to declare the namespace in `~/Views/web.config` if you are using the Razor view engine. – Darin Dimitrov Jul 17 '12 at 15:08

score 0 · Answer 2 · answered Jul 17 '12 at 14:57

0

Is the error occurring when running in VS debugger, or from a test or production system? Make sure your module containing the extension is properly installed (and updated properly). Also, try running "iisreset" from the command prompt.

answered Jul 17 '12 at 14:57

Les

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Unable to use extension method within partial view

2 Answers2