namespace System.Web.ModelBinding {
 
    public static class ModelBinders {
 
        private static readonly ModelBinderDictionary _binders = CreateDefaultBinderDictionary();
 
        public static ModelBinderDictionary Binders {
            get {
                return _binders;
            }
        }
#if UNDEF
        internal static IModelBinder GetBinderFromAttributes(Type type, Func<string> errorMessageAccessor) {
            AttributeCollection allAttrs = TypeDescriptorHelper.Get(type).GetAttributes();
            CustomModelBinderAttribute[] filteredAttrs = allAttrs.OfType<CustomModelBinderAttribute>().ToArray();
            return GetBinderFromAttributesImpl(filteredAttrs, errorMessageAccessor);
        }
 
        internal static IModelBinder GetBinderFromAttributes(ICustomAttributeProvider element, Func<string> errorMessageAccessor) {
            CustomModelBinderAttribute[] attrs = (CustomModelBinderAttribute[])element.GetCustomAttributes(typeof(CustomModelBinderAttribute), true /* inherit */);
            return GetBinderFromAttributesImpl(attrs, errorMessageAccessor);
        }
 
        private static IModelBinder GetBinderFromAttributesImpl(CustomModelBinderAttribute[] attrs, Func<string> errorMessageAccessor) {
            // this method is used to get a custom binder based on the attributes of the element passed to it.
            // it will return null if a binder cannot be detected based on the attributes alone.
 
            if (attrs == null) {
                return null;
            }
 
            switch (attrs.Length) {
                case 0:
                    return null;
 
                case 1:
                    IModelBinder binder = attrs[0].GetBinder();
                    return binder;
 
                default:
                    string errorMessage = errorMessageAccessor();
                    throw new InvalidOperationException(errorMessage);
            }
        }
#endif
        private static ModelBinderDictionary CreateDefaultBinderDictionary() {
            // We can't add a binder to the HttpPostedFileBase type as an attribute, so we'll just
            // prepopulate the dictionary as a convenience to users.
 
            ModelBinderDictionary binders = new ModelBinderDictionary() {
#if UNDEF
                { typeof(HttpPostedFileBase), new HttpPostedFileBaseModelBinder() },
                { typeof(byte[]), new ByteArrayModelBinder() },
                { typeof(Binary), new LinqBinaryModelBinder() }
#endif
            };
            return binders;
        }
 
    }
}