在Blazor WASM中，如果授权策略无法生效，可能是由于未正确配置授权服务导致的。

解决方法可以如下：

1. 创建一个实现了IAuthorizationService接口的自定义授权服务，用于在应用程序中处理授权相关的逻辑。例如，在该服务中实现了授权策略的添加、删除和验证。

public class CustomAuthorizationService : IAuthorizationService
{
  private readonly AuthorizationPolicyProvider _policyProvider;

  public CustomAuthorizationService(AuthorizationPolicyProvider policyProvider)
  {
    _policyProvider = policyProvider;
  }

  public async Task AuthorizeAsync(ClaimsPrincipal user, object resource, IEnumerable requirements)
  {
    // 实现授权验证逻辑
  }

  public async Task GetPolicyAsync(string policyName)
  {
    return await _policyProvider.GetPolicyAsync(policyName);
  }

  public async Task AuthorizeAsync(ClaimsPrincipal user, object resource, string policyName)
  {
    var policy = await _policyProvider.GetPolicyAsync(policyName);
    var result = await _policyProvider.AuthorizeAsync(user, resource, policy);
    return result.Succeeded;
  }
}

2. 注册自定义授权服务，并配置策略映射。授权服务的注册方法可以复写项目中的Program.cs文件中的CreateHostBuilder()方法，进行配置即可。

builder.Services.AddScoped();
builder.Services.AddSingleton();
builder.Services.AddSingleton();
builder.Services.AddSingleton();
builder.Services.AddSingleton();

builder.Services.AddAuthorization(options =>
{
    options.FallbackPolicy = new AuthorizationPolicyBuilder()
        .RequireAuthenticatedUser()
        .Build();
        
    options.AddPolicy("MyCustomPolicy", policy =>
        policy.RequireAssertion(context => true)
    );
});

3. 在组件中使用授权策略。例如，你可以在Razor组件中使用AuthorizeView组件，以根据用户是否具有所需权限来展示不同的UI。

  
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