下载文件,我得到Content-Length标头是无效的

时间:2010-03-02 17:41:36

标签: c# asp.net httpwebrequest httpwebresponse

我正在使用下面的代码从网络服务器下载文件,并收到此错误:

错误: 从URL保存文件时出错:服务器提交了协议违规。

Section = ResponseHeader Detail ='Content-Length'标头值无效

在运行Fiddler时,它会说:

Content-Length响应头不是有效的无符号整数 内容长度:13312583

守则:

public static bool SaveFileFromURL(string url, string destinationFileName, int timeoutInSeconds)
        {
            //SetAllowUnsafeHeaderParsing20();
            Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
            SettingsSection section = (SettingsSection)config.GetSection("system.net/settings");
            section.HttpWebRequest.UseUnsafeHeaderParsing = false;
            config.Save();

            // Create a web request to the URL
            HttpWebRequest MyRequest = (HttpWebRequest)WebRequest.Create(url);
            MyRequest.UseDefaultCredentials = true;
            MyRequest.ContentLength = 0;

            MyRequest.Timeout = timeoutInSeconds * 1000;
            try
            {
                // Get the web response
                HttpWebResponse MyResponse = (HttpWebResponse)MyRequest.GetResponse();

                // Make sure the response is valid
                if (HttpStatusCode.OK == MyResponse.StatusCode)
                {
                    // Open the response stream
                    using (Stream MyResponseStream = MyResponse.GetResponseStream())
                    {
                        // Open the destination file
                        using (FileStream MyFileStream = new FileStream(destinationFileName, FileMode.OpenOrCreate, FileAccess.Write))
                        {
                            // Create a 4K buffer to chunk the file
                            byte[] MyBuffer = new byte[4096];
                            int BytesRead;
                            // Read the chunk of the web response into the buffer
                            while (0 < (BytesRead = MyResponseStream.Read(MyBuffer, 0, MyBuffer.Length)))
                            {
                                // Write the chunk from the buffer to the file
                                MyFileStream.Write(MyBuffer, 0, BytesRead);
                            }
                        }
                    }
                }
            }
            catch (Exception err)
            {
                throw new Exception("Error saving file from URL:" + err.Message, err);
            }
            return true;
        }

更新:如果我直接将URL传递到浏览器,则会成功下载该文件,并且会在GetResponse行上抛出错误。

更新2 :我在WebClient.Downloadfile中遇到同样的错误:

public static bool DL_Webclient(string url, string destinationFileName)
{
    WebClient myWebClient = new WebClient();
    myWebClient.UseDefaultCredentials = true;
    myWebClient.DownloadFile(url, destinationFileName);

    return true;
}

更新3 :检索到邮件中的其他标头(使用Fiddler)后,它们是:

HTTP/1.1 200 OK
Connection: close
Date: Wed, 03 Mar 2010 08:43:06 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 13314320
Content-Type: application/x-evsaveset
Set-Cookie: ASPSESSIONIDQQCQSCRC=CFHHJHADOIBCFAFOHFJCDNEG; path=/
Cache-control: private

2 个答案:

答案 0 :(得分:0)

是否还有其他HTTP标头?

它可能与“Transfer-Encoding”标头或类似规则有关。有关这些标头及其对Content-Length标头的影响的更多具体信息,请参阅W3C websiteMore W3C website

希望这有帮助,

答案 1 :(得分:0)

你能不能使用WebClient.DownloadFile吗?