How can I implement policy based authorization in Blazor?

The AuthorizeView component supports policy-based authorization. You can use the Policy parameter for policy-based authorization.

<AuthorizeView Policy="IsShowContent">
   <p>You can only see the content if enabled the IsShowContent policy.</p>
</AuthorizeView>

Policy based authorization in Asp.Net Core

The policies are registered in the application Startup classes ConfigureServices method.

public void ConfigureServices(IServiceCollection services)
    {
        services.AddAuthorization(config =>
        {
            config.AddPolicy("IsShowContent", policy => policy.RequireClaim("IsShowContent", "true"));
        });
    }