CODEWITHSUNDEEP
c#asp.netenums
user1108948
user1108948

Reputation:

Create an enumeration of URLs - Error: Identifer expected

Shamed by this simple question. For some reason, I want to put all asp.net URLs in an enum. But I got an error: identifer expected

My code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Admin.Code
{
    public enum url
    {
       /_layouts/Admin/test1.aspx,
       /_layouts/Admin/test2.aspx,
       /_layouts/Admin/test3.aspx
    }

    class AdminUrlSettings
    {
    }
}

Thanks.

Upvotes: 2

Views: 2728

Answers (4)

Msonic
Msonic

Reputation: 1456

These aren't valid enum identifiers. You'll need string enumerations. Here's an example

You will be able to do something like this:

public enum url
{
    [StringValue("/_layouts/Admin/test1.aspx")]
    Test1,
    [StringValue("/_layouts/Admin/test2.aspx")]
    Test2,
    [StringValue("/_layouts/Admin/test3.aspx")]
    Test3
}

Upvotes: 2

KeithS
KeithS

Reputation: 71573

Here's something I've done many times to turn enumerated values into "friendly strings". You can also use it to create "string-valued" enums. It's in the same vein as Msonic's solution, but the attribute is built into the Framework.

public enum url
{
   [Description(@"/_layouts/Admin/test1.aspx")] Test1,
   [Description(@"/_layouts/Admin/test2.aspx")] Test2,
   [Description(@"/_layouts/Admin/test2.aspx")] Test3
}

...

public static string GetDescription(this Enum enumValue)
{
    object[] attr = enumValue.GetType().GetField(enumValue.ToString())
            .GetCustomAttributes(typeof (DescriptionAttribute), false);
        if (attr.Length > 0)
            return ((DescriptionAttribute) attr[0]).Description;

        return enumValue.ToString();
}

//usage
Response.Redirect(url.Test1.GetDescription());

Upvotes: 3

JaredPar
JaredPar

Reputation: 754763

Identifiers in C# can't contain / characters. They are limited to underscores, letters and numbers (and possibly a @ prefix). To fix this you need to make the enum values valid C# identifiers

enum url {
  test1,
  test2,
  test3
}

Later turning these into an actual valid url can be done with a switch statement over the value

public static string GetRelativeUrl(url u) {
  switch (u) {
    case url.test1:
      return "/_layouts/Admin/test1.aspx";
    case url.test2:
      return "/_layouts/Admin/test2.aspx";
    case url.test3:
      return "/_layouts/Admin/test3.aspx";
    default: 
      // Handle bad URL, possibly throw
      throw new Exception();
  }
}

Upvotes: 1

Jacob
Jacob

Reputation: 995

Enums don't really work like that. Valid identifiers work the same way variable names do (ie. a combination of letters, numbers and underscores not beginning with a number). Why not just use a list:

List<string> urls = new List<string>{"/_layouts/Admin/test1.aspx", "/_layouts/Admin/test2.aspx", "/_layouts/Admin/test3.aspx"}

or use slightly different identifiers:

public enum url
{
     layout_Admin_test1,
     layout_Admin_test2,
     layout_Admin_test3
}

Upvotes: 0

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