page header documentation has been added.

docs/en/UI/Blazor/Page-Header.md

@@ -1,3 +1,90 @@
 # Blazor UI: Page Header
 
-TODO
+You can use the`PageHeader` component to set the page title, the breadcrumb items and the toolbar items for a page. Before using the `PageHeader` component, you need to add a using statement for the `Volo.Abp.AspNetCore.Components.Web.Theming.Layout` namespace.
+
+Once you add the `PageHeader` component to your page, you can control the related values using the parameters. 
+
+## Page Title
+
+ You can use the `Title` parameter to control the page header.
+
+```csharp
+<PageHeader Title="Book List">
+</PageHeader>
+```
+
+## Breadcrumb
+
+> **The [Basic Theme](Basic-Theme.md) currently doesn't implement the breadcrumbs.**
+
+Breadcrumbs can be added using the `BreadcrumbItems` property.
+
+**Example: Add Language Management to the breadcrumb items.**
+
+Create a collection of `Volo.Abp.BlazoriseUI.BreadcrumbItem` objects and set the collection to the `BreadcrumbItems` parameter.
+
+```csharp
+public partial class Index
+{
+    protected List<BreadcrumbItem> BreadcrumbItems { get; } = new();
+
+    protected override void OnInitialized()
+    {
+        BreadcrumbItems.Add(new BreadcrumbItem("Language Management"));
+    }
+}
+```
+
+Navigate back to the razor page.
+
+```csharp
+<PageHeader BreadcrumbItems="@BreadcrumbItems" /> 
+```
+
+The theme then renders the breadcrumb. An example render result can be:
+
+![breadcrumbs-example](../../images/breadcrumbs-example.png)
+
+* The Home icon is rendered by default. Set `BreadcrumbShowHome` to `false` to hide it.
+* Breadcrumb items will be activated based on current navigation. Set `BreadcrumbShowCurrent` to `false` to disable it.
+
+You can add as many items as you need. `BreadcrumbItem` constructor gets three parameters:
+
+* `text`: The text to show for the breadcrumb item.
+* `url` (optional): A URL to navigate to, if the user clicks to the breadcrumb item.
+* `icon` (optional): An icon class (like `fas fa-user-tie` for Font-Awesome) to show with the `text`.
+
+## Page Toolbar
+
+Page toolbar can be set using the `Toolbar` property.
+
+**Example: Add  a "New Item" toolbar item to the page toolbar.**
+
+Create a `PageToolbar` object and define toolbar items using the `AddButton` extension method. 
+
+```csharp
+public partial class Index
+{
+    protected PageToolbar Toolbar { get; } = new();
+    
+    protected override void OnInitialized()
+    {
+        Toolbar.AddButton("New Item", () =>
+        {
+            //Write your click action here
+            return Task.CompletedTask;
+        }, icon:IconName.Add);
+    }
+}
+```
+
+Navigate back to the razor page and set the `Toolbar` parameter.
+
+```csharp
+<PageHeader Toolbar="@Toolbar"  /> 
+```
+
+An example render result can be:
+
+![breadcrumbs-example](../../images/page-header-toolbar-blazor.png)
+