c# - Why are extensions not available in @helper? -

i created view extension this:

namespace myproject {     public static class pageextensions     {         public static htmlstring myext(this webviewpage page)         { 

so can type in razor view:

@this.myext() 

please note views include namespace declared via web.config:

<system.web.webpages.razor>   <pages pagebasetype="system.web.mvc.webviewpage">     <namespaces>       <add namespace="myproject" /> 

everything good. want write @helper function , use extension there:

@helper myhelper() {     var page = (webviewpage) currentpage;     <div>         @page.myext()     </div> } 

but extension not available there. error is:

compiler error message: cs1061: 'system.web.mvc.webviewpage' not contain definition 'myext' , no extension method 'myext' accepting first argument of type 'system.web.mvc.webviewpage' found (are missing using directive or assembly reference?)

what missing?

make sure web.config modified "/views/web.config"