Source Code for DataAnnotationsModelMetadataProvider

For some reason, .NET Reflector throws an exception when I tr开发者_高级运维y to reflect on this class. It works for everything else.

What is the source code of DataAnnotationsModelMetadataProvider, please?

Feel free to download the ASP.NET MVC source code and inspect the implementation. Here's how it looks in ASP.NET MVC 3 RTM:

namespace System.Web.Mvc {
    using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.ComponentModel.DataAnnotations;
    using System.Linq;

    public class DataAnnotationsModelMetadataProvider : AssociatedMetadataProvider {

        protected override ModelMetadata CreateMetadata(IEnumerable<Attribute> attributes, Type containerType, Func<object> modelAccessor, Type modelType, string propertyName) {
            List<Attribute> attributeList = new List<Attribute>(attributes);
            DisplayColumnAttribute displayColumnAttribute = attributeList.OfType<DisplayColumnAttribute>().FirstOrDefault();
            DataAnnotationsModelMetadata result = new DataAnnotationsModelMetadata(this, containerType, modelAccessor, modelType, propertyName, displayColumnAttribute);

            // Do [HiddenInput] before [UIHint], so you can override the template hint
            HiddenInputAttribute hiddenInputAttribute = attributeList.OfType<HiddenInputAttribute>().FirstOrDefault();
            if (hiddenInputAttribute != null) {
                result.TemplateHint = "HiddenInput";
                result.HideSurroundingHtml = !hiddenInputAttribute.DisplayValue;
            }

            // We prefer [UIHint("...", PresentationLayer = "MVC")] but will fall back to [UIHint("...")]
            IEnumerable<UIHintAttribute> uiHintAttributes = attributeList.OfType<UIHintAttribute>();
            UIHintAttribute uiHintAttribute = uiHintAttributes.FirstOrDefault(a => String.Equals(a.PresentationLayer, "MVC", StringComparison.OrdinalIgnoreCase))
                                           ?? uiHintAttributes.FirstOrDefault(a => String.IsNullOrEmpty(a.PresentationLayer));
            if (uiHintAttribute != null) {
                result.TemplateHint = uiHintAttribute.UIHint;
            }

            DataTypeAttribute dataTypeAttribute = attributeList.OfType<DataTypeAttribute>().FirstOrDefault();
            if (dataTypeAttribute != null) {
                result.DataTypeName = dataTypeAttribute.ToDataTypeName();
            }

            EditableAttribute editable = attributes.OfType<EditableAttribute>().FirstOrDefault();
            if (editable != null) {
                result.IsReadOnly = !editable.AllowEdit;
            }
            else {
                ReadOnlyAttribute readOnlyAttribute = attributeList.OfType<ReadOnlyAttribute>().FirstOrDefault();
                if (readOnlyAttribute != null) {
                    result.IsReadOnly = readOnlyAttribute.IsReadOnly;
                }
            }

            DisplayFormatAttribute displayFormatAttribute = attributeList.OfType<DisplayFormatAttribute>().FirstOrDefault();
            if (displayFormatAttribute == null && dataTypeAttribute != null) {
                displayFormatAttribute = dataTypeAttribute.DisplayFormat;
            }
            if (displayFormatAttribute != null) {
                result.NullDisplayText = displayFormatAttribute.NullDisplayText;
                result.DisplayFormatString = displayFormatAttribute.DataFormatString;
                result.ConvertEmptyStringToNull = displayFormatAttribute.ConvertEmptyStringToNull;

                if (displayFormatAttribute.ApplyFormatInEditMode) {
                    result.EditFormatString = displayFormatAttribute.DataFormatString;
                }

                if (!displayFormatAttribute.HtmlEncode && String.IsNullOrWhiteSpace(result.DataTypeName)) {
                    result.DataTypeName = DataTypeUtil.HtmlTypeName;
                }
            }

            ScaffoldColumnAttribute scaffoldColumnAttribute = attributeList.OfType<ScaffoldColumnAttribute>().FirstOrDefault();
            if (scaffoldColumnAttribute != null) {
                result.ShowForDisplay = result.ShowForEdit = scaffoldColumnAttribute.Scaffold;
            }

            DisplayAttribute display = attributes.OfType<DisplayAttribute>().FirstOrDefault();
            string name = null;
            if (display != null) {
                result.Description = display.GetDescription();
                result.ShortDisplayName = display.GetShortName();
                result.Watermark = display.GetPrompt();
                result.Order = display.GetOrder() ?? ModelMetadata.DefaultOrder;

                name = display.GetName();
            }

            if (name != null) {
                result.DisplayName = name;
            }
            else {
                DisplayNameAttribute displayNameAttribute = attributeList.OfType<DisplayNameAttribute>().FirstOrDefault();
                if (displayNameAttribute != null) {
                    result.DisplayName = displayNameAttribute.DisplayName;
                }
            }

            RequiredAttribute requiredAttribute = attributeList.OfType<RequiredAttribute>().FirstOrDefault();
            if (requiredAttribute != null) {
                result.IsRequired = true;
            }

            return result;
        }
    }
}