Bug 6230 - System.ComponentModel.DataAnnotations.RequiredAttribute not permitted on parameters
Summary: System.ComponentModel.DataAnnotations.RequiredAttribute not permitted on para...
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: unspecified
Hardware: All All
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-07-22 21:24 UTC by Greg Najda
Modified: 2012-07-26 07:50 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Greg Najda 2012-07-22 21:24:12 UTC
The following compiles on .NET, but not Mono:

using System;
using System.ComponentModel.DataAnnotations;

namespace RequiredAttributeTest
    class Program
        static void Main(string[] args)

        static void SomeFunc([Required] int someParam)

The error when compiling on Mono is "/home/greg/dev/RequiredAttributeTest/RequiredAttributeTest/Main.cs(31,31): Error CS0592: The attribute `System.ComponentModel.DataAnnotations.RequiredAttribute' is not valid on this declaration type. It is valid on `property, indexer, field' declarations only (CS0592) (RequiredAttributeTest)"

It appears that [Required] became applicable to parameters in .NET 4.0. I ran into this while trying to test an ASP.NET MVC application on Mono. I assume all that's needed is to change the AttributeUsage of RequiredAttribute.
Comment 1 Marek Safar 2012-07-26 07:50:02 UTC
Fixed in master