Shared MVC Razor functions in several views

Question

I have functions in my view that is shared by several pages:

@functions 
{
    public HtmlString ModeImage(ModeEnum mode) 
    {
        switch(mode)
        {
            case AMode: new HtmlString("<img etc..."); break;
            // more etc...
        }
    }
}

Is there a way to have it in a separate file and include it on each page without having to copy and paste it in to each one. I know I can write a .cs file and access it per page, but the function really concerns the view and I'de hate to have to recompile if this function changes.

@Miro: That won't work. Pages don't inherit anything from their layout pages. After all, `Layout` is set at runtime. — SLaks, Jun 14 '11 at 17:49
See http://stackoverflow.com/questions/17602507/using-a-razor-functions-in-several-webpages-cshtml-files if you really need to reuse the same function over several distinct views. — rsenna, Jan 24 '14 at 14:08

score 46 · Answer 1 · answered Nov 12 '14 at 02:51

46

(Here's a more detailed version of the existing answers.)

Create a folder called App_Code in the root of the MVC project if it doesn't already exist. In here, create an empty razor view and name it whatever you want:

MVC project with Razor view called Shared.cshtml inside App_Code folder

Add @helpers and/or static methods to it as needed:

@helper ShowSomething()
{
    <span>Something</span>
}

@functions
{
    public static int CalculateSomething()
    {
        return 1;
    }
}

Then use them from your views by first accessing the shared view by name:

@Shared.ShowSomething()
@Shared.CalculateSomething()

answered Nov 12 '14 at 02:51

Sam

40,644
36
176
219

That's awesome. Can you do the same for an Area? Basically, not shared across the whole codebase, but rather just one section? – twsmale Sep 29 '16 at 17:03
@twsmale, I don't know; I haven't really used areas before. Maybe you could make a new question for that. – Sam Sep 29 '16 at 21:24
up for explaining in detail about the difference between helper and functions and the way to use them – jet_choong Feb 06 '18 at 16:37
3

now, we cannot share functions in dotnet core `.net6` like this – Rahul Ranjan Jan 19 '23 at 16:54

score 20 · Accepted Answer · edited Jun 14 '11 at 17:39

20

This sounds like you want the Razor @helper methods described in the blog post ASP.NET MVC3 and the @helper syntax within Razor by Scott Guthrie.

Here is the overview... "The @helper syntax within Razor enables you to easily create re-usable helper methods that can encapsulate output functionality within your view templates. They enable better code reuse, and can also facilitate more readable code."

edited Jun 14 '11 at 17:39

vcsjones

138,677
31
291
286

answered Jun 14 '11 at 17:28

Paige Cook

22,415
3
57
68

It doesn't look like he wants a helper (he's returning void) – SLaks Jun 14 '11 at 17:31
Sorry, it is sort of a helper method which returns an image html depending on an enum. I feel like its too little for a partial and I don't want code to be recompiled if I say, change the icon name. This looks like what I'm looking for. Going to try it out first. – kailoon Jun 14 '11 at 18:16
That was perfect. =) I didn't know this existed. Thank you very much. – kailoon Jun 14 '11 at 18:23
This is useful, but helpers have some limitations such as lack of generics, and you can still reuse static methods across multiple views. – Sam Nov 12 '14 at 02:25

score 4 · Answer 3 · answered Jun 14 '11 at 17:26

4

You could make a static helper page and put a normal static method in the page.
You could then call it by writing PageName.MyMethod() anywhere, and I believe that you won't need to recompile the project.

answered Jun 14 '11 at 17:26

SLaks

868,454
176
1,908
1,964

Shared MVC Razor functions in several views

3 Answers3

Linked