WebRequest在ASP.NET应用程序中失败,"414 Request URI太长"

Question

我们有一个ASP.NET应用程序,它在将报告的参数作为WebRequest传递后,以HTML格式请求SSRS 2005报告.只有在请求具有大量多选参数的报表时,应用程序才会失败,从而在该webRequest.GetResponse()行处抛出"414:Request URI too long"错误.

用于发出请求的代码是:

HttpWebRequest webRequest = null;
HttpWebResponse webResponse = null;
string webRequestURL = _ReportManager.GetRSUrl(reportID); //this passes the report link on the SSRS server

//make the request

Byte[] bytes = Encoding.UTF8.GetBytes("xml_doc=" + HttpUtility.UrlEncode(webRequestURL));

webRequest = (HttpWebRequest)WebRequest.Create(webRequestURL);
webRequest.Method = "POST";
webRequest.ContentLength = bytes.Length;
webRequest.Timeout = Configuration.WebRequestTimeOut;

RSExecution2005.ReportExecutionService rsE = new RSExecution2005.ReportExecutionService();
rsE.Url = Configuration.ReportExecutionServiceUrl2005;
rsE.Credentials = System.Net.CredentialCache.DefaultCredentials;
webRequest.Credentials = rsE.Credentials;

Stream reqStream = null;
reqStream = webRequest.GetRequestStream();
reqStream.Write(bytes, 0, bytes.Length);
reqStream.Close();

webResponse = (HttpWebResponse)webRequest.GetResponse();

由于报告在服务器端失败,我已经查看了IIS和ReportServer属性,以字节方式增加maxUrl,maxRequestLength,MaxQueryString等(根据本文),但应用程序仍然会抛出错误.我已经在web.config文件中尝试过这个并直接在IIS管理器上.

2005年的报告服务器版本,它托管在运行IIS 7的Windows Server 2008上.

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在David Lively的建议中,我尝试通过将参数放在正文中来请求URI.这适用于较小的请求,但仍然无法用于大型多选参数.修订后的代码如下:

HttpWebRequest webRequest = null;
HttpWebResponse webResponse = null;
string webRequestURL = _ReportManager.GetRSUrl(reportID); //this passes the report link on the SSRS server

string postData = string.Empty;
string URIrequest = string.Empty;
URIrequest = webRequestURL.Substring(0, webRequestURL.IndexOf("&"));
int requestLen = webRequestURL.Length;
int postDataStart = webRequestURL.IndexOf("&") + 1;
postData = webRequestURL.Substring(postDataStart, (requestLen - postDataStart));

Byte[] bytes1 = Encoding.UTF8.GetBytes(postData);

webRequest = (HttpWebRequest)WebRequest.Create(URIrequest);
                webRequest.Method = "POST";
                webRequest.ContentType = "application/x-www-form-urlencoded";
                webRequest.ContentLength = bytes1.Length;
                webRequest.Timeout = Configuration.WebRequestTimeOut;

RSExecution2005.ReportExecutionService rsE = new RSExecution2005.ReportExecutionService();
rsE.Url = Configuration.ReportExecutionServiceUrl2005;
rsE.Credentials = System.Net.CredentialCache.DefaultCredentials;
webRequest.Credentials = rsE.Credentials;

Stream reqStream = webRequest.GetRequestStream();
reqStream.Write(bytes1, 0, bytes1.Length);
reqStream.Close();
webResponse = (HttpWebResponse)webRequest.GetResponse();

即使webRequest的requestURI不存储参数,似乎GetReponse()函数也将参数添加到webRequest的'address'属性中.这可能是问题吗？如果是的话,怎么解决呢.

Answer 1

您是否可以使用POST变量而不是GET？这样,我没有任何限制,因为所有数据都将以数据包而不是HTTP标头发送.

实际上,您可能正在使用代码中的POST.您是否可以查看服务器日志以验证导致此失败的URI？如果您要发送POST数据,请求uri不应成为问题,除非它与您正在发布的数据无关.

Answer 2

由于您已经在使用 POST 来获取报告，因此我建议您将当前在请求正文中的查询字符串中传递的参数放入其中。查询字符串参数适用于有限数量的参数，但不适用于大量项目。