如果你试图访问 HttpContext，那么你可以使用 IHttpContextAccessor 来达到这个目的.

If you are trying to access HttpContext, then you can use IHttpContextAccessor for this purpose.

例子:

services.AddTransient<QueryValueService>();

public class QueryValueService
{
    private readonly IHttpContextAccessor _accessor;

    public QueryValueService(IHttpContextAccessor httpContextAccessor)
    {
        _accessor = httpContextAccessor;
    }

    public string GetValue()
    {
        return _accessor.HttpContext.Request.Query["value"];
    }
}

请注意，在上面的示例中，QueryValueService 应仅注册为 Transient 或 Scoped 而不是 SingletonHttpContext 是基于每个请求的...

Note that in the above example QueryValueService should be registered only as Transient or Scoped and not Singleton as HttpContext is per-request based...