Program.cs

using System;
using System.Resources;

namespace PostSharp.Samples.ValidateResourceString
{
  internal class Program
  {
    private const string resourceName = "PostSharp.Samples.ValidateResourceString.MyResource";

    private static readonly ResourceManager resourceManager = new ResourceManager(resourceName,
      typeof(Program).Assembly);

    private static void Main(string[] args)
    {
      // These two method calls are valid.
      Console.WriteLine(GetResourceString("String1"));
      Console.WriteLine(GetResourceString("String2"));

      // There is a warning for the following line because Strong3 is not a valid string name.
      Console.WriteLine(GetResourceString("Strong3"));
    }

    private static string GetResourceString([ValidateResourceString(resourceName)] string key)
    {
      return resourceManager.GetString(key) ?? "*** Error ***";
    }
  }
}