CSDN:http://blog.csdn.net/huwei2003/article/details/53559272
设置了也没有用，于是想到手动清理应用程序池，但又迁配置问题于是改成最后的方式！
protected void StartStopRecycleApp(string method) ???{ ???????string AppPoolName = this.tbAppName.Text.Trim(); ???????//string method = "Recycle"; ???????try ???????{ ???????????DirectoryEntry appPool = new DirectoryEntry("IIS://localhost/W3SVC/AppPools"); ???????????DirectoryEntry findPool = appPool.Children.Find(AppPoolName, "IIsApplicationPool"); ???????????findPool.Invoke(method, null); ???????????appPool.CommitChanges(); ???????????appPool.Close(); ???????????lbMsg.Text = string.Format("应用程序池{0}{1}成功", AppPoolName,method); ???????} ???????catch (Exception ex) ???????{ ???????????lbMsg.Text = string.Format("应用程序池{0}{2}失败:{1}", AppPoolName, ex.Message,method); ???????} ???}tbAppName是一个textbox，用来输入应用程序池的名字，如“DefaultAppPool”。
当method="Recycle"时就是回收，为“Start”时是启动，为“Stop”时是停止。
注意：
1. 必须引入System.DirectoryServices包
2. 运行此程序的应用程序也的用户必须权限比较高，可以单独为此程序提供应用程序程，或者建立一个虚拟目录在配制里模拟高级用户（如administrators或者system），否则应用程序会抛出“拒绝访问”的异常。
var filePath=Server.MapPath("~/_UploadFile/" + paths[0]); ???????????if (File.Exists(filePath)) ???????????{ ???????????????try ???????????????{ ???????????????????FileInfo info = new FileInfo(filePath); ???????????????????long fileSize = info.Length; ???????????????????HttpContext.Current.Response.Clear(); ???????????????????//指定Http Mime格式为压缩包 ???????????????????HttpContext.Current.Response.ContentType = "application/x-zip-compressed"; ???????????????????// Http 协议中有专门的指令来告知浏览器, 本次响应的是一个需要下载的文件. 格式如下: ???????????????????// Content-Disposition: attachment;filename=filename.txt ???????????????????HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(paths[1], System.Text.Encoding.UTF8)); ???????????????????//不指明Content-Length用Flush的话不会显示下载进度 ??????????????????????HttpContext.Current.Response.AddHeader("Content-Length", fileSize.ToString()); ???????????????????HttpContext.Current.Response.TransmitFile(filePath, 0, fileSize); ???????????????????HttpContext.Current.Response.Flush(); ???????????????} ???????????????catch ???????????????{ } ???????????????finally ???????????????{ ???????????????????HttpContext.Current.Response.Close(); ???????????????} ???????????????//byte[] buffer = null; ???????????????//using (FileStream stream = new FileStream(Server.MapPath("~/_UploadFile/" + paths[0]), FileMode.Open, FileAccess.Read)) ???????????????//{ ???????????????// ???if (stream.Length > 1000000) { ???????????????// ???????StartStopRecycleApp("Recycle"); ???????????????// ???} ???????????????// ???buffer = new byte[stream.Length]; ???????????????// ???stream.Read(buffer, 0, buffer.Length); ???????????????// ???stream.Close(); ???????????????//} ???????????????//if (buffer != null) ???????????????//{ ???????????????// ???Response.Clear(); ???????????????// ???Response.Charset = "gb2312"; ???????????????// ???Response.ContentType = "application/octet-stream"; ???????????????// ???Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(paths[1], System.Text.Encoding.UTF8)); ???????????????// ???Response.AddHeader("Content-Length", file.fileSize.ToString()); ???????????????// ???Response.BinaryWrite(buffer); ???????????????// ???Response.Flush(); ???????????????// ???Response.End(); ???????????????//} ???????????}文件下载报错：引发类型为“System.OutOfMemoryException”的异常-.Net 内存溢出
原文地址：http://www.cnblogs.com/xiaoruilin/p/7424318.html