AreaControllerFactory

AreaControllerFactory.cs

public class AreaControllerFactory : IControllerFactory
{
    private Dictionary<string, string> m_areaPartMapping = new Dictionary<string, string>();
    private ReaderWriterLockSlim m_rwLock = new ReaderWriterLockSlim();
    private Dictionary<string, Type> m_controllerTypes = new Dictionary<string, Type>();

    public string NamespaceBase { get; private set; }

    public AreaControllerFactory(string namespaceBase)
        : this(namespaceBase, null)
    { }

    public AreaControllerFactory(string namespaceBase, IDictionary<string, string> areaPartMapping)
    {
        this.NamespaceBase = namespaceBase.EndsWith(".") ? namespaceBase : namespaceBase + ".";

        if (areaPartMapping != null)
        {
            foreach (var pair in areaPartMapping)
            {
                this.m_areaPartMapping.Add(pair.Key.ToLowerInvariant(), pair.Value);
            }
        }
    }

    public IController CreateController(RequestContext requestContext, string controllerName)
    {
        Type controllerType;
        object area;
        if (requestContext.RouteData.Values.TryGetValue("area", out area))
        {
            controllerType = this.GetControllerType(area.ToString(), controllerName);
        }
        else
        {
            controllerType = this.GetControllerType(null, controllerName);
        }

        if (controllerType == null)
        {
            throw new HttpException(404,
                String.Format(
                    "Controller of path {0} not found.",
                    requestContext.HttpContext.Request.Path));
        }

        try
        {
            return (IController)Activator.CreateInstance(controllerType);
        }
        catch (Exception ex)
        {
            string message = String.Format("Error creating controller {0}" + controllerType);
            throw new InvalidOperationException(message, ex);
        }
    }

    private string GetNamespacePart(string area)
    {
        if (String.IsNullOrEmpty(area)) return "";

        string part;
        if (this.m_areaPartMapping.TryGetValue(area.ToLowerInvariant(), out part))
        {
            return part;
        }

        return area;
    }

    private Type GetControllerType(string area, string controllerName)
    {
        string part = this.GetNamespacePart(area);

        string typeName = String.IsNullOrEmpty(part) ?
            this.NamespaceBase + controllerName.ToLowerInvariant() + "Controller" :
            this.NamespaceBase + part + "." + controllerName.ToLowerInvariant() + "Controller";

        Type type;

        this.m_rwLock.EnterReadLock();
        try
        {
            if (this.m_controllerTypes.TryGetValue(typeName, out type))
            {
                return type;
            }
        }
        finally
        {
            this.m_rwLock.ExitReadLock();
        }

        type = Type.GetType(typeName, false, true);

        if (type != null)
        {
            this.m_rwLock.EnterWriteLock();
            try
            {
                this.m_controllerTypes[typeName] = type;
            }
            finally
            {
                this.m_rwLock.ExitWriteLock();
            }
        }

        return type;
    }

    public void ReleaseController(IController controller)
    {
        IDisposable disposable = controller as IDisposable;
        if (disposable != null)
        {
            disposable.Dispose();
        }
    }
}