C#多线程实现异步接口

interface ITest
{
    /// <summary>
    /// 方法的返回类型是Task<T>
    /// </summary>
    /// <returns></returns>
    Task<string> GetAsync();
}

/// <summary>
 /// 定义接口
 /// </summary>
 interface ITest
 {
     /// <summary>
     /// 方法的返回类型是Task<T>
     /// </summary>
     /// <returns></returns>
     ///不能标注为async
    Task<string> GetAsync();
 }

 public class Test : ITest
 {
     /// <summary>
     /// 方法不标注为async 返回一个Task<string>类型
     /// </summary>
     /// <returns></returns>
     //public Task<string> GetAsync()
     //{
     //    return Task.Run<string>(() => 
     //    {
     //        return "2";
     //    });
     //}

     /// <summary>
     /// 方法标注为async 直接返回一个string类型
     /// </summary>
     /// <returns></returns>
     public async Task<string> GetAsync()
     {
         return "3";
     }
 }