C# - The HttpRequest Class
The HttpRequest class is under System.Web namespace. It contains properties and methods necessary to handle an HTTP request. It contains all information passed by the browser, including all form variables, certificates and header information. It also contains the CGI server variables.
Properties and Methods of the HttpRequest Class
| Item | Description |
| Properties | |
| AcceptTypes | Contains a list of supported Multipurpose Internet Mail Extensions (MIME) accept types |
| ApplicationPath | Contains the application root path |
| Browser | Contains information about the browser that is performing the request |
| ClientCertificate | Contains the client security certificate for the current request |
| ContentEncoding | Contains the character set of the current request |
| ContentLength | Contains the length of the content sent by the browser for the current request |
| ContentType | Contains the MIME content type for the current request |
| Cookies | Contains the collection of cookies sent by the browser |
| FilePath | Contains the virtual path of the application |
| Files | Contains the names of the files uploaded by the browser |
| Form | Contains the collection of form variables |
| Headers | Contains the collection of HTTP headers |
| HttpMethod | Contains the HTTP data transfer method |
| IsAuthenticated | Contains True if the user has been authenticated |
| IsSecureConnection | Contains True if the current request was made over a secure connection |
| Params | Contains a combines collection of QueryString, Form, ServerVariable, and Cookie collections |
| Path | Contains the virtual path for the current request |
| PathInfo | Contains additional path information |
| PhysicalApplicationPath | Contains the physical disk location of the root directory for the application |
| PhysicalPath | Contains the physical disk location of the requested uniform resource locator (URL) |
| QueryString | Contains a collection of querystring values for the current request |
| RawUrl | Contains the complete, unmodified URL for the current request |
| RequestType | Contains the data transfer method for the current request |
| ServerVariables | Contains a collection of Web server variables |
| TotalBytes | Contains the total number of bytes of the current request |
| Url | Contains information about the URL of the current request |
| UrlReferer | Contains information about the previous request |
| UserAgent | Contains the contents of the user-agent string, as sent by the browser |
| UserHostAddress | Contains the remote Internet Protocol (IP) address of the client |
| UserHostName | Contains the remote host name of the client |
| UserLanguages | Contains a string array of client language preferences |
| Methods | |
| MapPath() | Maps a virtual path to the actual physical path for the current request |
| SaveAs() | Saves the entire HTTP request to disk |
HttpRequest.AcceptTypes
Syntax
String[] AcceptTypes
Description
The AcceptTypes property contains an array of all accepted MIME types
Example
int index;
string output;
String[] myArray = Request.AcceptTypes;
for(index = 0; index < myArray.Length; index++){
output = "Accept Type " + index + ": " + myArray[index] + "<br>";
}
HttpRequest.ApplicationPath
Syntax
String ApplicationPath
Description
The ApplicationPath property contains the virtual path of the application.
Example
string AppPath = Request.ApplicationPath;
HttpRequest.Browser
Syntax
HttpBrowserCapabilities Browser
Description
The Browser object contains information about the capabilities of the browser that is making the request.
Example
HttpBrowserCapabilities BrowCaps = new HttpBrowserCapabilities(); BrowCaps = Request.Browser;
HttpRequest.ClientCertificate
Syntax
HttpClientCertificate ClientCertificate
Description
The ClientCertificate property returns an object containing information about the client's security certificate.
Example
Object clientCertificate = Request.ClientCertificate;
HttpRequest.ContentEncoding
Syntax
Encoding ContentEncoding
Description
The ContentEncoding property contains an object with information about the character set of the client.
Example
String EncodingType; EncodingType = Request.ContentEncoding.EncodingName;
HttpRequest.ContentLength
Syntax
String ContentLength
Description
The ContentLength property contains the length of the entire client request.
Example
String contentLength = Request.ContentLength;
HttpRequest.ContentType
Syntax
String ContentType;
Description
The ContentType property contains information about the MIME content type of the client making the request.
Example
String contentType = Request.ContentType;
HttpRequest.Cookies
Syntax
HttpCookieCollection Cookies
Description
The Cookies property contains a collection of all the cookies passed by the client in the current request.
Example
HttpCookieCollection cookies = Request.Cookies;
HttpRequest.FilePath
Syntax
String FilePath
Description
The FilePath property contains the virtual path of the current request. The information returned does not contain any querystring information appended to the end of the URL.
Example
string filepath = Request.FilePath;
HttpRequest.Files
Syntax
HttpFileCollection Files
Description
The Files property contains a collection of files uploaded by the client in the current request. This collection is populated only if the client uploads files.
Example
<% @Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<html>
<head>
<script language="C#" runat="server">
void Page_Load(Object Source, EventArgs E){
if(IsPostBack == true){
string[] fileArray = new string[Request.Files.Count];
fileArray = Request.Files.AllKeys;
//For simplicity of presentation, only look at first file
fileName.Text = Request.Files.Get(0).FileName;
fileSize.Text = Request.Files.Get(0).ContentLength.ToString();
fileType.Text = Request.Files.Get(0).ContentType;
try{
Request.Files.Get(0).SaveAs(txtSaveLocation.Text);
}catch(Exception e){ }
}
}
</script>
</head>
<body>
<h1>Uploading Files</h1>
<form enctype="multipart/form-data" runat="server">
<p>
File to Upload: <br>
<input type="file" id="fileupload" runat="server">
</p>
<p>
Location to Save on Server (including file name): <br>
<asp:TextBox id="txtSaveLocation" runat="server"></asp:TextBox><br>
<input type="submit">
</p>
<p>
<h2>File Information</h2>
<b>File Name:</b> <asp:label id="fileName" runat="server"></asp:label><br>
<b>File Size:</b> <asp:label id="fileSize" runat="server"></asp:label><br>
<b>File Type:</b> <asp:label id="fileType" runat="server"></asp:label><br>
</p>
</form>
</body>
</html>
HttpRequest.Form
Syntax
NameValueCollection Form
Description
The Form property is a collection of all form values passed from the client during the submission of a form.
Example
string formValue = Request.Form["txtName"];
HttpRequest.Headers
Syntax
NameValueCollection Headers
Description
The Headers property is a collection of all the headers passed by the client in the request.
Example
string contentLength = Request.Headers["Content-Length"];
HttpRequest.HttpMethod
Syntax
String HttpMethod
Description
The HttpMethod property is used to determine the type of data transfer method used by the form. The three possible values are GET, POST, and HEAD.
Example
string requestMethod = Request.HttpMethod;
HttpRequest.IsAuthenticated
Syntax
Boolean IsAuthenticated
Description
The IsAuthenticated property contains True if the remote user has been authenticated.
Example
Boolean isAuthenticated = Request.IsAuthenticated;
HttpRequest.IsSecureConnection
Syntax
Boolean IsSecureConnection
Description
The IsSecureConnection property contains True if the current request was made over a secure connection (that is, the URL starts with https://).
Example
Boolean IsSecureConnection = Request.IsSecureConnection;
HttpRequest.Params
Syntax
NameValueCollection Params
Description
The Params property contains a combined collection of all querystring, form, cookie, and server variables submitted with the current request.
Example
string output;
for(int i=0; i < Request.Params.Count; i++)
output += Request.Params[i] + "<br>";
HttpRequest.Path
Syntax
String Path
Description
The Path property contains the virtual path for the current request.
Example
string virtualPath = Request.Path;
HttpRequest.PathInfo
Syntax
String PathInfo
Description
The PathInfo property contains additional path information for the current request. Specifically, the PathInfo property is empty unless the requested URL jas a tail with appended information.
Example
string pathInfo = Request.PathInfo;
HttpRequest.PhysicalApplicationPath
Syntax
String PhysicalApplicationPath
Description
The PhysicalApplicationPath property contains the physical file system directory of the current application.
Example
string appPath = Request.PhysicalApplicationPath;
HttpRequest.PhysicalPath
Syntax
String PhysicalPath
Description
The PhysicalPath property contains the physical file system path of the current request.
Example
string physicalPath = Request.PhysicalPath;
HttpRequest.QueryString
Syntax
NameValueCollection QueryString
Description
The QueryString property is a collection of all querystring items in the current request.
Example
string myName = Request.QueryString["txtName"];
HttpRequest.RawUrl
Syntax
String RawUrl
Description
The RawUrl property contains the entire URL for the current request. If the URL is http://www.triconsole.com/index.php?auth=true, then the RawUrl property is /index.php?auth=true.
Example
string rawUrl = Request.RawUrl;
HttpRequest.RequestType
Syntax
String RequestType
Description
The RequestType property contains the data transfer method for the current request. The value contains GET or POST.
Example
string requestType = Request.RequestType;
HttpRequest.ServerVariables
Syntax
NameValueCollection ServerVariables
Description
The ServerVariables property contains a collection of all the Web server variables for the current request.
Example
string output = ""; for(int i=0; i < Request.ServerVariables.Count; i++) output += Request.ServerVariables[i] + "<br>";
HttpRequest.TotalBytes
Syntax
Int32 TotalBytes
Description
The TotalBytes property contains the size of the current request, in bytes.
Example
int totalBytes = Request.TotalBytes;
HttpRequest.Url
Syntax
Uri Url
Description
The Url property returns an object of type Uri (defined in the System namespace).
Example
Uri UrlInfo = Request.Url; string absolutePath = UrlInfo.AbsolutePath;
HttpRequest.UrlReferrer
Syntax
Uri UrlReferrer
Description
The UrlReferrer property contains information about the referring URL (that is, the page the user was visiting before accessing the current page).
Example
Uri UrlReferrerInfo = Request.Url; string absolutePath = UrlReferrerInfo.AbsolutePath;
HttpRequest.UserAgent
Syntax
String UserAgent
Description
The UserAgent property contains the entire user-agent header for the browser that is making the request. For the version of Microsoft Internet Explorer that ships with Windows 2000, the user-agent is Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0; COM+ 1.0.2615).
Example
string userAgent = Request.UserAgent;
HttpRequest.UserHostAddress
Syntax
String UserHostAddress
Description
The UserHostAddress property contains the IP Address of the remote client that is making the request.
Example
string remoteAddr = Request.UserHostAddress;
HttpRequest.UserHostName
Syntax
String UserHostName
Description
The UserHostName property contains the remote Domain Name Server (DNS) host name of the client that is performing the current request.
Example
string remoteHost = Request.UserHostName;
HttpRequest.UserLanguages
Syntax
String[] UserLanguages
Description
The UserLanguages property contains a string array of the language preferences of the client.
Example
string output = "";
for(int i=0; i < Request.UserLanguages.Length; i++)
output = output + Request.UserLanguages[i] + "<br>";
HttpRequest.MapPath()
Syntax
String MapPath(String virtualPath)
String MapPath(String virtualPath, String baseVirtualDir, Boolean allowCrossAppMapping)
Description
The MapPath() method accepts a string containing a virtual path and returns the actual physical application directory for the virtual path.
Example
string rootIisPath = MapPath("/");
HttpRequest.SaveAs()
Syntax
void SaveAs(String filename, Boolean includeHeaders)
Description
The SaveAs() method saves the entire request to disk. The first argument is a string containing a physical disk location. If the second argument is true, then the headers will be saved to disk as well. The SaveAs() method could be used to save a client request to disk in the case of an error so that it could be fully debugged later.
Example
Request.SaveAs("c:\\temp\\entireRequest.txt", true);