DefaultDisplayTemplates.cs

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Web.Mvc.Properties;
using System.Web.UI.WebControls;

namespace System.Web.Mvc.Html
{
    internal static class DefaultDisplayTemplates
    {
        internal static string BooleanTemplate(HtmlHelper html)
        {
            bool? value = null;
            if (html.ViewContext.ViewData.Model != null)
            {
                value = Convert.ToBoolean(html.ViewContext.ViewData.Model, CultureInfo.InvariantCulture);
            }

            return html.ViewContext.ViewData.ModelMetadata.IsNullableValueType
                       ? BooleanTemplateDropDownList(value)
                       : BooleanTemplateCheckbox(value ?? false);
        }

        private static string BooleanTemplateCheckbox(bool value)
        {
            TagBuilder inputTag = new TagBuilder("input");
            inputTag.AddCssClass("check-box");
            inputTag.Attributes["disabled"] = "disabled";
            inputTag.Attributes["type"] = "checkbox";
            if (value)
            {
                inputTag.Attributes["checked"] = "checked";
            }

            return inputTag.ToString(TagRenderMode.SelfClosing);
        }

        private static string BooleanTemplateDropDownList(bool? value)
        {
            StringBuilder builder = new StringBuilder();

            TagBuilder selectTag = new TagBuilder("select");
            selectTag.AddCssClass("list-box");
            selectTag.AddCssClass("tri-state");
            selectTag.Attributes["disabled"] = "disabled";
            builder.Append(selectTag.ToString(TagRenderMode.StartTag));

            foreach (SelectListItem item in DefaultEditorTemplates.TriStateValues(value))
            {
                builder.Append(SelectExtensions.ListItemToOption(item));
            }

            builder.Append(selectTag.ToString(TagRenderMode.EndTag));
            return builder.ToString();
        }

        internal static string CollectionTemplate(HtmlHelper html)
        {
            return CollectionTemplate(html, TemplateHelpers.TemplateHelper);
        }

        internal static string CollectionTemplate(HtmlHelper html, TemplateHelpers.TemplateHelperDelegate templateHelper)
        {
            object model = html.ViewContext.ViewData.ModelMetadata.Model;
            if (model == null)
            {
                return String.Empty;
            }

            IEnumerable collection = model as IEnumerable;
            if (collection == null)
            {
                throw new InvalidOperationException(
                    String.Format(
                        CultureInfo.CurrentCulture,
                        MvcResources.Templates_TypeMustImplementIEnumerable,
                        model.GetType().FullName));
            }

            Type typeInCollection = typeof(string);
            Type genericEnumerableType = TypeHelpers.ExtractGenericInterface(collection.GetType(), typeof(IEnumerable<>));
            if (genericEnumerableType != null)
            {
                typeInCollection = genericEnumerableType.GetGenericArguments()[0];
            }
            bool typeInCollectionIsNullableValueType = TypeHelpers.IsNullableValueType(typeInCollection);

            string oldPrefix = html.ViewContext.ViewData.TemplateInfo.HtmlFieldPrefix;

            try
            {
                html.ViewContext.ViewData.TemplateInfo.HtmlFieldPrefix = String.Empty;

                string fieldNameBase = oldPrefix;
                StringBuilder result = new StringBuilder();
                int index = 0;

                foreach (object item in collection)
                {
                    Type itemType = typeInCollection;
                    if (item != null && !typeInCollectionIsNullableValueType)
                    {
                        itemType = item.GetType();
                    }
                    ModelMetadata metadata = ModelMetadataProviders.Current.GetMetadataForType(() => item, itemType);
                    string fieldName = String.Format(CultureInfo.InvariantCulture, "{0}[{1}]", fieldNameBase, index++);
                    string output = templateHelper(html, metadata, fieldName, null /* templateName */, DataBoundControlMode.ReadOnly, null /* additionalViewData */);
                    result.Append(output);
                }

                return result.ToString();
            }
            finally
            {
                html.ViewContext.ViewData.TemplateInfo.HtmlFieldPrefix = oldPrefix;
            }
        }

        internal static string DecimalTemplate(HtmlHelper html)
        {
            if (html.ViewContext.ViewData.TemplateInfo.FormattedModelValue == html.ViewContext.ViewData.ModelMetadata.Model)
            {
                html.ViewContext.ViewData.TemplateInfo.FormattedModelValue = String.Format(CultureInfo.CurrentCulture, "{0:0.00}", html.ViewContext.ViewData.ModelMetadata.Model);
            }

            return StringTemplate(html);
        }

        internal static string EmailAddressTemplate(HtmlHelper html)
        {
            return String.Format(CultureInfo.InvariantCulture,
                                 "<a href=\"mailto:{0}\">{1}</a>",
                                 html.AttributeEncode(html.ViewContext.ViewData.Model),
                                 html.Encode(html.ViewContext.ViewData.TemplateInfo.FormattedModelValue));
        }

        internal static string HiddenInputTemplate(HtmlHelper html)
        {
            if (html.ViewContext.ViewData.ModelMetadata.HideSurroundingHtml)
            {
                return String.Empty;
            }
            return StringTemplate(html);
        }

        internal static string HtmlTemplate(HtmlHelper html)
        {
            return html.ViewContext.ViewData.TemplateInfo.FormattedModelValue.ToString();
        }

        internal static string ObjectTemplate(HtmlHelper html)
        {
            return ObjectTemplate(html, TemplateHelpers.TemplateHelper);
        }

        internal static string ObjectTemplate(HtmlHelper html, TemplateHelpers.TemplateHelperDelegate templateHelper)
        {
            ViewDataDictionary viewData = html.ViewContext.ViewData;
            TemplateInfo templateInfo = viewData.TemplateInfo;
            ModelMetadata modelMetadata = viewData.ModelMetadata;
            StringBuilder builder = new StringBuilder();

            if (modelMetadata.Model == null)
            {
                // DDB #225237
                return modelMetadata.NullDisplayText;
            }

            if (templateInfo.TemplateDepth > 1)
            {
                // DDB #224751
                string text = modelMetadata.SimpleDisplayText;
                if (modelMetadata.HtmlEncode)
                {
                    text = html.Encode(text);
                }

                return text;
            }

            foreach (ModelMetadata propertyMetadata in modelMetadata.Properties.Where(pm => ShouldShow(pm, templateInfo)))
            {
                if (!propertyMetadata.HideSurroundingHtml)
                {
                    string label = propertyMetadata.GetDisplayName();
                    if (!String.IsNullOrEmpty(label))
                    {
                        builder.AppendFormat(CultureInfo.InvariantCulture, "<div class=\"display-label\">{0}</div>", label);
                        builder.AppendLine();
                    }

                    builder.Append("<div class=\"display-field\">");
                }

                builder.Append(templateHelper(html, propertyMetadata, propertyMetadata.PropertyName, null /* templateName */, DataBoundControlMode.ReadOnly, null /* additionalViewData */));

                if (!propertyMetadata.HideSurroundingHtml)
                {
                    builder.AppendLine("</div>");
                }
            }

            return builder.ToString();
        }

        private static bool ShouldShow(ModelMetadata metadata, TemplateInfo templateInfo)
        {
            return
                metadata.ShowForDisplay
                && metadata.ModelType != typeof(EntityState)
                && !metadata.IsComplexType
                && !templateInfo.Visited(metadata);
        }

        internal static string StringTemplate(HtmlHelper html)
        {
            return html.Encode(html.ViewContext.ViewData.TemplateInfo.FormattedModelValue);
        }

        internal static string UrlTemplate(HtmlHelper html)
        {
            return String.Format(CultureInfo.InvariantCulture,
                                 "<a href=\"{0}\">{1}</a>",
                                 html.AttributeEncode(html.ViewContext.ViewData.Model),
                                 html.Encode(html.ViewContext.ViewData.TemplateInfo.FormattedModelValue));
        }
    }
}