StreamWriter的资源释放不了

Question

现在有一个用C#写的windows service，每一分钟执行一次，其中有一个写log日志的方法：
        String path;
        FileStream log;
        StreamWriter writer;        public void writeLog(LogLevel outLevel, String[] data)
        {
            lock (lockobj)
            {                if (level <= (int)outLevel)
                {
                    try
                    {
                        String rotatePath;
                        if (path.Contains("_D_A_T_E_"))
                        {
                            rotatePath = path.Replace("_D_A_T_E_", "_" + DateTime.Now.ToString("yyyyMMdd"));
                        }
                        else if (path.Contains("_M_O_N_T_H_"))
                        {
                            rotatePath = path.Replace("_M_O_N_T_H_", "_" + DateTime.Now.ToString("yyyyMM"));
                        }
                        else
                        {
                            rotatePath = path;
                        }
                        log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read);
                        writer = new StreamWriter(log);                        writer.Write(
                            "[" + System.DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss") + "] " +
                            "[" + outLevel + "] ");                        writer.Write("[");                        StringBuilder sb = new StringBuilder();
                        foreach (String str in data)
                        {
                            sb.Append(str + ",");
                        }
                        writer.Write(sb.ToString().TrimEnd(','));
                        writer.Write("]\n");
                        writer.Flush();
                        writer.Close();
                        writer.Dispose();
                    }
                    catch
                    {
                    }
                }
            }
        } 现在的问题是：writer = new StreamWriter(log);
writer 对象生成后，资源释放不了，用perfmon监视查看，内存消耗差不多每一分钟都有增长。
其他所有的都注释掉了，单单运行log输出这一块。
GC.SuppressFinalize(this);
using(writer = new StreamWriter(log)){ }
都试过，还是不行
想问一下如何能彻底释放掉write的资源，谢谢

Answer 1

1、用log4net写日志。2、log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read); log没释放
  writer = new StreamWriter(log);
改为
using(log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read);)
{
        ...
     log.close();
}

Answer 2

把
   String path;
  FileStream log;
  StreamWriter writer;
宣告到方法裹头
应该是会释放掉的~

Answer 3

不只log没释放的原因，曾经这样写过：
                        using (log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read))
                        {
                            using (writer = new StreamWriter(log))
                            {
                                writer.Write(
                                    "[" + System.DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss") + "] " +
                                    "[" + outLevel + "] ");                                writer.Write("[");                                StringBuilder sb = new StringBuilder();
                                foreach (String str in data)
                                {
                                    sb.Append(str + ",");
                                }
                                writer.Write(sb.ToString().TrimEnd(','));
                                writer.Write("]\n");
                                writer.Flush();
                                writer.Close();
                                writer.Dispose();
                                log.Flush();
                                log.Close();
                                log.Dispose();
                            }
                        }
还是没用的。
把有关write的内容注释掉，只留有log部分，内存变量不变。
所以感觉和log部分无关。

Answer 4

不要把文件流之类的定义为成员变量，因为这些流，一般需要用完后立即释放
把你中间的代码改了下            try
            {
                using (FileStream log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read))
                {
                    using (StreamWriter writer = new StreamWriter(log))
                    {
                        writer.Write(
                        "[" + System.DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss") + "] " +
                        "[" + outLevel + "] ");                        writer.Write("[");                        StringBuilder sb = new StringBuilder();
                        foreach (String str in data)
                        {
                            sb.Append(str + ",");
                        }
                        writer.Write(sb.ToString().TrimEnd(','));
                        writer.Write("]\n");
                        writer.Flush();
                        writer.Close();
                        writer.Dispose();
                    }
                    log.Close();
                    log.Dispose();
                }
            }
            catch(Exception ex)
            {
                Console.WriteLine(ex.Message);
            }

Answer 5

  FileStream log;
  StreamWriter writer;
写到函数头试试看还有
  writer.Close();
  writer.Dispose();写到finally里面比较好
if (writer != null) {
writer.Close();
writer.Dispose();
}我个人觉得这些法没有问题
lock (lockobj)，但是前提是lockobj是个静态变量，或者该log操作类只有唯一一个实例

Answer 6

那你用玩之后把 
log.close();
log = null;
writer .close();
writer = null;
这个样子呢

Answer 7

通过上面的了解，感觉不像是这个函数的问题，你这样试试：public void writeLog(LogLevel outLevel, String[] data)屏蔽这个函数里面所有执行代码！看看还有这种现象没？个人觉得是外部的参数String[] data造成！

Answer 8

        public void writeLog(LogLevel outLevel, String[] data)
        {
            FileStream log;
            StreamWriter writer;            lock (lockobj)
            {                if (level <= (int)outLevel)
                {
                    try
                    {
                        String rotatePath;
                        if (path.Contains("_D_A_T_E_"))
                        {
                            rotatePath = path.Replace("_D_A_T_E_", "_" + DateTime.Now.ToString("yyyyMMdd"));
                        }
                        else if (path.Contains("_M_O_N_T_H_"))
                        {
                            rotatePath = path.Replace("_M_O_N_T_H_", "_" + DateTime.Now.ToString("yyyyMM"));
                        }
                        else
                        {
                            rotatePath = path;
                        }
                        log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read);
                        //writer = new StreamWriter(log);                        //writer.Write(
                        //    "[" + System.DateTime.Now.ToString("yyyy/MM/dd HH:mm:ss") + "] " +
                        //    "[" + outLevel + "] ");                        //writer.Write("[");                        //StringBuilder sb = new StringBuilder();
                        //foreach (String str in data)
                        //{
                        //    sb.Append(str + ",");
                        //}
                        //writer.Write(sb.ToString().TrimEnd(','));
                        //writer.Write("]\n");
                        //writer.Flush();
                        //writer.Close();                    }
                    catch
                    {
                    }
                }
            }
        }
如果把write的部分注释掉，运行的话，内存是不增加的

Answer 9

把这两家代码：
  log = new FileStream(rotatePath, FileMode.Append, FileAccess.Write, FileShare.Read);
  writer = new StreamWriter(log);放到类的构造函数！

Answer 10

我建议使用的时候只用  Using（）
                            ｛
                             ｝

Answer 11

LZ 我看你 log实例化之后 后面的代码都没将log干掉。会不会是这个原因。

Answer 12

试了，不是正解，放到构造函数后，只第一次能出力log,后面的就都不能出力了

Answer 13

不是，我也曾认为是这个原因，加了   log.Flush();
   log.Close();
   log.Dispose();
但没有效果，不是这个原因

Answer 14

如果楼主以上方式都试过
那就不知道什么原因了，这种情况没遇到过。
把写日志的方法写成一个类 
然后
  String path;
  FileStream log;
  StreamWriter writer;
  没必要是全局的。
  如果在不行（就log4net），实在不想用就请高手请教，我也学习下。