AssemblyResourceManager.cs :  » Development » devAdvantage » AnticipatingMinds » PlatformServices » Globalization » C# / CSharp Open Source

using System;
using System.IO;
using System.Resources;
using System.Reflection;
using System.Collections;


namespace AnticipatingMinds.PlatformServices.Globalization{
  /// <summary>
  /// Provides access to assembly based resources.
  /// </summary>
  /// <remarks>
  /// AssemblyResourceManager is a wrapper arounf ResourceManager class. The main differentiator though that 
  /// it organizes all the code to instatiate and managed Resourcemanager in one place.
  /// AssemblyResourceManager also caches instances of ResourceManager class per assembly/resourcebase basis. 
  /// Though accessing cache requires some reflection code (aquiring calling assembly) it still 
  /// speeds up creation of ResourceManager. 
  /// Organizing all the code for managing Resourcemanager in one place also facilitates better code reuse 
  /// and enables single point of failure.
  /// </remarks>
  public class AssemblyResourceManager
  {
    /// <summary>
    /// Initializes new instance of AssemblyResourceManager.
    /// </summary>
    /// <remarks>This constaractor is private because AssemblyResourceManager is a singleton and 
    /// it cannot be instantiated from the outside world.</remarks>
    /// <param name="resourceBaseName">The root name of the resources. For example, the root name for the resource file named "MyResource.en-US.resources" is "MyResource".</param>
    /// <param name="resourceAssembly">The main Assembly for the resources.</param>
    private AssemblyResourceManager(string resourceBaseName, Assembly resourceAssembly)
    {
      resourceManager = new ResourceManager(resourceBaseName,resourceAssembly);
      this.resourceAssembly = resourceAssembly;
    }

    /// <summary>
    /// Instantiates ResourceManager base on resource name. Assembly is assumed to 
    /// be calling assembly.
    /// </summary>
    /// <param name="resourceBaseName">The root name of the resources. For example, the root name for the resource file named "MyResource.en-US.resources" is "MyResource".</param>
    /// <returns>AssemblyResourceManager instance.</returns>
    public static AssemblyResourceManager GetInstance(string resourceBaseName)
    {
      return GetInstance(resourceBaseName,Assembly.GetCallingAssembly());
    }

    /// <summary>
    /// Instantiates ResourceManager base on resource name and main resource assembly.
    /// </summary>
    /// <param name="resourceBaseName">The root name of the resources. For example, the root name for the resource file named "MyResource.en-US.resources" is "MyResource".</param>
    /// <param name="mainResourceAssembly">The main Assembly for the resources.</param>
    /// <returns>AssemblyResourceManager instance.</returns>
    public static AssemblyResourceManager GetInstance(string resourceBaseName, Assembly mainResourceAssembly)
    {
      string key = resourceBaseName + mainResourceAssembly.FullName;

      AssemblyResourceManager resourceManagerInstance = (AssemblyResourceManager) resourceManagersCache[key];
      if(resourceManagerInstance == null)
      {
        resourceManagerInstance = new AssemblyResourceManager(resourceBaseName,mainResourceAssembly);
        resourceManagersCache.Add(key,resourceManagerInstance);
      }

      return resourceManagerInstance;
    }

    /// <summary>
    /// Gets the value of the specified String resource for the current culture.
    /// </summary>
    /// <param name="stringId">Id of string resource.</param>
    /// <returns>Returns the value of the specified String resource.</returns>
    public string GetString(string stringId)
    {
      string translatedString = resourceManager.GetString(stringId);
      if(translatedString == null)
        return "!"+stringId + "!"; //indicate that translation is missing
      else
        return translatedString;
    }

    /// <summary>
    /// Gets formatted value of the specified String resource for the current culture.
    /// </summary>
    /// <param name="stringId">Id of string resource.</param>
    /// <param name="arguments">Arguments for formatting destenation string.</param>
    /// <returns>Returns the value of the specified String resource formatted with provided arguments.</returns>
    public string GetFormatedString(string stringId,params object[] arguments)
    {
      string resourceString = resourceManager.GetString(stringId);
      if(resourceString == null)
        resourceString = stringId;

      if(arguments.Length == 0)
        return resourceString;
      else
      {
        return String.Format(resourceString,arguments);
      }
    }

    /// <summary>
    /// Gets the value of the specified Object resource for the current culture.
    /// </summary>
    /// <param name="resourceId">Resource id.</param>
    /// <returns>Returns the value of the specified Object resource.</returns>
    public object GetObject(string resourceId)
    {
      return resourceManager.GetObject(resourceId);
    }

    /// <summary>
    /// Gets the resourse stream from assembly manifest.
    /// </summary>
    /// <param name="resourceName">Resource name.</param>
    /// <returns>Resource stream.</returns>
    public Stream GetManifestResourceStream(string resourceName)
    {
      return resourceAssembly.GetManifestResourceStream(resourceName);
    }

    private static Hashtable resourceManagersCache = new Hashtable();
    private ResourceManager resourceManager = null;
    private Assembly resourceAssembly;
  }
}