C# 通过HttpWebRequest 创建连接获取文件大小 判断Http类型的文件是否存在

 1 public void DisposeReportData(SynFileInfo item)
 2         {
 3             MReport report = new MReport();
 4             report.文件名 = item.DocName;
 5             report.URL = item.DownPath;
 6             HttpWebRequest request = null;
 7             HttpWebResponse response = null;
 8             try
 9             {
10                 request = WebRequest.Create(item.DownPath) as HttpWebRequest;
11                 request.Proxy = null;//不使用代理 .NET4.0中的默认代理是开启的
12                 request.KeepAlive = false;//不建立持久性连接
13                 request.Timeout = 5000;//连接网址的超时时间
14                 request.ReadWriteTimeout = 5000;//读取网址内容的超时时间      
15                 response = request.GetResponse() as HttpWebResponse;
16                 long length = response.ContentLength;
17                 string size = FileOperate.GetAutoSizeString(length, 2);
18                 report.大小 = size;
19                 report.连接状态 = "有 效";
20             }
21             catch (WebException webEx)
22             {
23                 report.大小 = "0 MB";
24                 report.连接状态 = "无 效";
25                 Console.WriteLine("请求的文件不存在!" + webEx.Message);
26             }
27             finally
28             {
29                 lock (ConfigReader.ReportData)
30                 {
31                     ConfigReader.ReportData.Add(report);
32                 }
33                 if (response != null)
34                 {
35                     response.Close();//关闭连接
36                 }
37                 if (request != null)
38                 {
39                     request.Abort();//中止请求
40                 }
41                 request = null;
42                 response = null;
43                 System.GC.Collect();//强制垃圾回收,并释放资源
44 
45             }
46         }