.Net WebApi 使用Session

直接使用Session 会报错“未将对象引用设置到对象的实例”。

解决办法：在Global中添加如下代码

        /// <summary>
        /// 打开session
        /// </summary>
        public override void Init()
        {
            this.PostAuthenticateRequest += (sender, e) => HttpContext.Current.SetSessionStateBehavior(SessionStateBehavior.Required);
            base.Init();
        }

Session帮助类：

  public class SessionHelper
     {
         /// <summary>
         /// 写Session
         /// </summary>
         /// <typeparam name="T">Session键值的类型</typeparam>
         /// <param name="key">Session的键名</param>
         /// <param name="value">Session的键值</param>
         public static void WriteSession<T>(string key, T value)
         {
             if (key.Length == )
                 return;
             HttpContext.Current.Session[key] = value;
             HttpContext.Current.Session.Timeout = ;//有效期为1分钟
         }

         /// <summary>
         /// 写Session
         /// </summary>
         /// <param name="key">Session的键名</param>
         /// <param name="value">Session的键值</param>
         public static void WriteSession(string key, string value)
         {
             WriteSession<string>(key, value);
         }

         /// <summary>
         /// 读取Session的值
         /// </summary>
         /// <param name="key">Session的键名</param>
         public static string GetSession(string key)
         {
             if (key.Length == )
                 return string.Empty;
             return HttpContext.Current.Session[key] as string;
         }

         /// <summary>
         /// 读取Session的值
         /// </summary>
         /// <param name="key">Session的键名</param>
         public static T GetSession<T>(string key)
         {
             if (key.Length == )
                 return default(T);
             return (T)HttpContext.Current.Session[key];
         }

         /// <summary>
         /// 删除指定Session
         /// </summary>
         /// <param name="key">Session的键名</param>
         public static void RemoveSession(string key)
         {
             if (key.Length == )
                 return;
             HttpContext.Current.Session.Contents.Remove(key);
         }
     }