!2382 fix(##I4RER0): update Ajax component

* 删除菜单中多余的Ajax菜单
* 添加Goto方法用于跳转
* 修复Ajax组件在失败时没有返回null，而是返回"null"字符串的BUG

src/BootstrapBlazor.Shared/Samples/Ajaxs.razor

@@ -16,3 +16,10 @@
     <Button OnClick="Fail">登录失败</Button>
     <Ajax></Ajax>
 </DemoBlock>
+
+<DemoBlock Introduction="用于Js实现页面跳转，解决了Blazor页面作为SPA跳转时不会真正刷新页面的问题" Title="页面跳转" Name="Normal">
+
+    <Button OnClick="Goto">跳转到文档首页</Button>
+	<Button OnClick="GotoSelf">跳转到自己（刷新页面）</Button>
+    <Ajax></Ajax>
+</DemoBlock>

src/BootstrapBlazor.Shared/Samples/Ajaxs.razor.cs

@@ -76,4 +76,14 @@ public partial class Ajaxs
             }
         }
     }
+
+    private async Task Goto()
+    {
+        await AjaxService.Goto("/introduction");
+    }
+
+    private async Task GotoSelf()
+    {
+        await AjaxService.Goto("/ajaxs");
+    }
 }

src/BootstrapBlazor.Shared/Shared/NavMenu.razor.cs

@@ -524,11 +524,6 @@ public sealed partial class NavMenu
                 Text = Localizer["Transition"],
                 Url = "transitions"
             },
-            new()
-            {
-                Text = "Ajax",
-                Url = "ajaxs"
-            },
         };
         AddBadge(item);
     }

src/BootstrapBlazor/Components/Ajax/Ajax.cs

@@ -23,6 +23,7 @@ public class Ajax : BootstrapComponentBase, IDisposable
     {
         base.OnInitialized();
         AjaxService.Register(this, GetMessage);
+        AjaxService.RegisterGoto(this, Goto);
     }
 
     private async Task<string?> GetMessage(AjaxOption option)
@@ -31,6 +32,11 @@ public class Ajax : BootstrapComponentBase, IDisposable
         return obj;
     }
 
+    private async Task Goto(string url)
+    {
+        await JSRuntime.InvokeVoidAsync(identifier: "$.bb_ajax_goto", url);
+    }
+
     /// <summary>
     /// Dispose 方法
     /// </summary>
@@ -39,6 +45,7 @@ public class Ajax : BootstrapComponentBase, IDisposable
         if (disposing)
         {
             AjaxService.UnRegister(this);
+            AjaxService.UnRegisterGoto(this);
         }
     }
 

src/BootstrapBlazor/Components/Ajax/Ajax.js

@@ -17,7 +17,13 @@
                     return null;
                 }
             });
+            if (res == null) {
+                return null;
+            }
             return JSON.stringify(res);
+        },
+        bb_ajax_goto: function (url) {
+            window.location.href = url;
         }
     });
 })(jQuery);

src/BootstrapBlazor/Components/Ajax/AjaxService.cs

@@ -23,6 +23,18 @@ public class AjaxService
     /// <param name="callback"></param>
     internal void Register(IComponent key, Func<AjaxOption, Task<string?>> callback) => Cache.Add((key, callback));
 
+    /// <summary>
+    /// 获得 跳转其他页面的回调委托缓存集合
+    /// </summary>
+    private List<(IComponent Key, Func<string, Task> Callback)> GotoCache { get; } = new();
+
+    /// <summary>
+    /// 注册服务
+    /// </summary>
+    /// <param name="key"></param>
+    /// <param name="callback"></param>
+    internal void RegisterGoto(IComponent key, Func<string, Task> callback) => GotoCache.Add((key, callback));
+
     /// <summary>
     /// 注销事件
     /// </summary>
@@ -35,6 +47,18 @@ public class AjaxService
         }
     }
 
+    /// <summary>
+    /// 注销事件
+    /// </summary>
+    internal void UnRegisterGoto(IComponent key)
+    {
+        var item = GotoCache.FirstOrDefault(i => i.Key == key);
+        if (item.Key != null)
+        {
+            GotoCache.Remove(item);
+        }
+    }
+
     /// <summary>
     /// 调用Ajax方法发送请求
     /// </summary>
@@ -45,4 +69,23 @@ public class AjaxService
         var cb = Cache.FirstOrDefault().Callback;
         return cb == null ? null : await cb.Invoke(option);
     }
+
+    /// <summary>
+    /// 调用Goto方法跳转其他页面
+    /// </summary>
+    /// <param name="url"></param>
+    public async 
+    /// <summary>
+    /// 调用Goto方法跳转其他页面
+    /// </summary>
+    /// <param name="url"></param>
+    Task
+Goto(string url)
+    {
+        var cb = GotoCache.FirstOrDefault().Callback;
+        if (cb != null)
+        {
+            await cb.Invoke(url);
+        }
+    }
 }