问题记录Delegate to an instance method cannot have null 'this'

最近在写Socket服务器程序，写了一个简易的消息队列用于数据入库，遇到了这样的问题“Delegate to an instance method cannot have null 'this'”。

代码如下：

  1 using System;
  2 using System.Collections;
  3 using System.Collections.Generic;
  4 using System.Threading;
  5 using AmtServer.Common;
  6 using System.Linq;
  7 
  8 namespace AmtServer.DAL
  9 {
 10     public class DBJobProcessor
 11     {
 12         public readonly static DBJobProcessor Instance = new DBJobProcessor();
 13         //任务列表
 14         private List<JobArgs> j_list = new List<JobArgs>();
 15         private bool isdoingwork = false;
 16         private Thread jobthrd = new Thread(new ThreadStart(Instance.DoWork));
 17         private DBJobProcessor()
 18         {
 19             try
 20             {
 21                 Start();
 22             }
 23             catch (Exception ex)
 24             {
 25                 LogHelper.Logger.Error(ex);
 26             }
 27         }
 28         /// <summary>
 29         /// 开启线程
 30         /// </summary>
 31         public void Start()
 32         {
 33             jobthrd.IsBackground = true;
 34             jobthrd.Start();
 35         }
 36         /// <summary>
 37         /// 停止线程
 38         /// </summary>
 39         public void Stop()
 40         {
 41             try
 42             {
 43                 jobthrd.Abort();
 44             }
 45             catch (System.Exception ex)
 46             {
 47                 LogHelper.Logger.Error(ex);
 48             }
 49         }
 50 
 51         private void DoWork()
 52         {
 53             try
 54             {
 55                 while (true)
 56                 {
 57                     if (j_list.Count > 0)
 58                     {
 59                         if (!isdoingwork)
 60                         {
 61                             List<JobArgs> templst;
 62                             lock (((ICollection)j_list).SyncRoot)
 63                             {
 64                                 int n = 0;
 65                                 if (j_list.Count > 200)
 66                                 {
 67                                     n = 200;
 68                                 }
 69                                 else
 70                                 {
 71                                     n = j_list.Count;
 72                                 }
 73                                 JobArgs[] temp = new JobArgs[n];
 74                                 j_list.CopyTo(0, temp, 0, n);
 75                                 templst = new List<JobArgs>(temp);
 76                                 j_list.RemoveRange(0, n);
 77                             }
 78                             DoWriteDB(templst.ToArray());
 79                         }
 80                     }
 81                     else
 82                     {
 83                         Thread.Sleep(10000);
 84                     }
 85                 }
 86             }
 87             catch (Exception ex)
 88             {
 89                 LogHelper.Logger.Error(ex);
 90             }
 91         }
 92         //执行数据库操作
 93         private void DoWriteDB(JobArgs[] ls)
 94         {
 95             try
 96             {
 97                 isdoingwork = true;
 98                 int result = 0;
 99                 result += DapDBHelper.Execute(Constant.SQL_Position_Upsert, DapDBHelper.constr, ls);
100                 LogHelper.Instance.ShowInfoLog($"插入{result}/{ls.Length}条");
101             }
102             catch (Exception ex)
103             {
104                 LogHelper.Logger.Error(ex);
105                 LogHelper.Instance.ShowInfoLog("DoWriteDB_Error:"+ex.Message);
106             }
107             finally
108             {
109                 isdoingwork = false;
110             }
111         }
112         /// <summary>
113         /// 添加任务
114         /// </summary>
115         /// <param name="job"></param>
116         public void AddJob(JobArgs job)
117         {
118             try
119             {
120                 lock (((ICollection)j_list).SyncRoot)
121                 {
122                     j_list.Add(job);
123                 }
124             }
125             catch (Exception ex)
126             {
127                 LogHelper.Logger.Error(ex);
128             }
129         }
130 
131     }
132 }

问题出现在16行，Instance实例的线程订阅了Instance的方法，自己订阅自己。

很惭愧到现在还出现这种低级问题，还是得看书，基础不能拉下啊。。

我们都是阴沟里的虫子，但总得有人仰望星空。