3

Folks,

I am MVC 2 newbie and stuck on this problem:

AccountModuls.cs

public class LogOnModel
{
[Required]
[DisplayName("User name")]
public string UserName { get; set; }
…
}

LogOn.aspx

<%: Html.LabelFor(m => m.UserName) %>

The text “User name” will be finally displayed in the website - based on my definition

[DisplayName("User name")].

No Problem.

But how can I change this text in AccountController.cs?

public ActionResult LogOn()
{   
return View();
}
user415876
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1 Answers1

8

You can't :) You have to change the DisplayName-attribute on the class in order for the .LabelFor helper to construct the label. You could of course just write out the HTML for the Label yourself if you want it to be something else.

Don't see why you would want to change the Displayname from page to page though? Am I misunderstanding something?

Edit:

Custom displayname attribute:

public class MyDisplayName : DisplayNameAttribute
{
    public int DbId { get; set; }

    public MyDisplayName(int DbId)
    {
        this.DbId = DbId;
    }


    public override string DisplayName
    {
        get
        {
            // Do some db-lookup to retrieve the name
            return "Some string from DBLookup";
        }
    }
}

public class TestModel
{
    [MyDisplayName(2)]
    public string MyTextField { get; set; }
}
Yngve B-Nilsen
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  • Thx 4 the very fast reply! The idea was to change it dynamically to have the chance to read it out of a DB. – user415876 Aug 10 '10 at 07:50
  • I've added some code for you.. You can create a derived attribute of your own to perform the db-lookup and just override the DisplayName-getter :) – Yngve B-Nilsen Aug 10 '10 at 08:03
  • remember to check the answer as correct if it does the job. Increases your chances og getting nice replies later on. :) – Yngve B-Nilsen Aug 10 '10 at 08:37
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    Thank you very much! This works realy fine for me now! (nd of course I checked the answer ;-) – user415876 Aug 12 '10 at 07:16
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    You should never do any db lookup (and any business logic) in an attribute. – starteleport Jan 29 '14 at 11:45
  • @starteleport Businesslogic no - but I don't agree that you shouldn't do any db-lookup in an attribute. – Yngve B-Nilsen Jan 29 '14 at 11:58
  • @starteleport could you elaborate as to why you shouldn't do any db-lookup? What if there is an API-Key in the Request-headers, that you want to translate into an authenticated user on each request? – Yngve B-Nilsen Jan 29 '14 at 12:19
  • @YngveB.Nilsen Imho, in your mentioned scenario it will be better to create plain request filter (and not FilterAttribute). One drawback of using filter attributes is that it's difficult to inject dependencies into them, and you'll probably need to do service-location to reach, say, DB from such a filter. This makes unit-testing more difficult. What is acceptable for me is filter attributes with some simple tasks like logging, maybe wrapping exceptions, etc. After all, attributes are primarily for embedding metadata to your types. – starteleport Jan 30 '14 at 06:22
  • @starteleport please keep in mind that the answer was written august 2010... It's a while ago :) – Yngve B-Nilsen Jan 31 '14 at 07:49