// 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; using System.Collections.Generic; using Microsoft.Extensions.Internal; namespace Microsoft.AspNetCore.Mvc.Razor { /// <summary> /// Key for entries in <see cref="RazorViewEngine.ViewLookupCache"/>. /// </summary> internal readonly struct ViewLocationCacheKey : IEquatable<ViewLocationCacheKey> { /// <summary> /// Initializes a new instance of <see cref="ViewLocationCacheKey"/>. /// </summary> /// <param>The view name or path.</param> /// <param>Determines if the page being found is the main page for an action.</param> public ViewLocationCacheKey( string viewName, bool isMainPage) : this( viewName, controllerName: null, areaName: null, pageName: null, isMainPage: isMainPage, values: null) { } /// <summary> /// Initializes a new instance of <see cref="ViewLocationCacheKey"/>. /// </summary> /// <param>The view name.</param> /// <param>The controller name.</param> /// <param>The area name.</param> /// <param>The page name.</param> /// <param>Determines if the page being found is the main page for an action.</param> /// <param>Values from <see cref="IViewLocationExpander"/> instances.</param> public ViewLocationCacheKey( string viewName, string controllerName, string areaName, string pageName, bool isMainPage, IReadOnlyDictionary<string, string> values) { ViewName = viewName; ControllerName = controllerName; AreaName = areaName; PageName = pageName; IsMainPage = isMainPage; ViewLocationExpanderValues = values; } /// <summary> /// Gets the view name. /// </summary> public string ViewName { get; } /// <summary> /// Gets the controller name. /// </summary> public string ControllerName { get; } /// <summary> /// Gets the area name. /// </summary> public string AreaName { get; } /// <summary> /// Gets the page name. /// </summary> public string PageName { get; } /// <summary> /// Determines if the page being found is the main page for an action. /// </summary> public bool IsMainPage { get; } /// <summary> /// Gets the values populated by <see cref="IViewLocationExpander"/> instances. /// </summary> public IReadOnlyDictionary<string, string> ViewLocationExpanderValues { get; } /// <inheritdoc /> public bool Equals(ViewLocationCacheKey y) { if (IsMainPage != y.IsMainPage || !string.Equals(ViewName, y.ViewName, StringComparison.Ordinal) || !string.Equals(ControllerName, y.ControllerName, StringComparison.Ordinal) || !string.Equals(AreaName, y.AreaName, StringComparison.Ordinal) || !string.Equals(PageName, y.PageName, StringComparison.Ordinal)) { return false; } if (ReferenceEquals(ViewLocationExpanderValues, y.ViewLocationExpanderValues)) { return true; } if (ViewLocationExpanderValues == null || y.ViewLocationExpanderValues == null || (ViewLocationExpanderValues.Count != y.ViewLocationExpanderValues.Count)) { return false; } foreach (var item in ViewLocationExpanderValues) { if (!y.ViewLocationExpanderValues.TryGetValue(item.Key, out var yValue) || !string.Equals(item.Value, yValue, StringComparison.Ordinal)) { return false; } } return true; } /// <inheritdoc /> public override bool Equals(object obj) { if (obj is ViewLocationCacheKey) { return Equals((ViewLocationCacheKey)obj); } return false; } /// <inheritdoc /> public override int GetHashCode() { var hashCodeCombiner = HashCodeCombiner.Start(); hashCodeCombiner.Add(IsMainPage ? 1 : 0); hashCodeCombiner.Add(ViewName, StringComparer.Ordinal); hashCodeCombiner.Add(ControllerName, StringComparer.Ordinal); hashCodeCombiner.Add(AreaName, StringComparer.Ordinal); hashCodeCombiner.Add(PageName, StringComparer.Ordinal); if (ViewLocationExpanderValues != null) { foreach (var item in ViewLocationExpanderValues) { hashCodeCombiner.Add(item.Key, StringComparer.Ordinal); hashCodeCombiner.Add(item.Value, StringComparer.Ordinal); } } return hashCodeCombiner; } } }
我们重点来看下其中的 Equals 方法，如下所示：