Gets or sets a collection of query name/value pairs associated with the request.
Assembly: System (in System.dll)
Property ValueType: System.Collections.Specialized.NameValueCollection
A NameValueCollection that contains query name/value pairs associated with the request. If no pairs are associated with the request, the value is an empty NameValueCollection.
The property contains a NameValueCollection instance containing name/value pairs that are appended to the URI as a query string. The contents of the property are preceded by a question mark (?), and name/value pairs are separated from one another by an ampersand (&).
The following code example takes user input from the command line and builds a NameValueCollection that is assigned to the property. It then downloads the response from the server to a local file.
Dim uriString As String = "http://www.contoso.com/search" ' Create a new WebClient instance. Dim myWebClient As New WebClient() ' Create a new NameValueCollection instance to hold the QueryString parameters and values. Dim myQueryStringCollection As New NameValueCollection() Console.Write(("Enter the word(s), separated by space characters, to search for in " + uriString + ": ")) ' Read user input phrase to search in uriString. Dim searchPhrase As String = Console.ReadLine() If searchPhrase.Length > 1 Then 'Assign the user-defined search phrase. myQueryStringCollection.Add("q", searchPhrase) ' If error, default to search 'Microsoft'. Else myQueryStringCollection.Add("q", "Microsoft") End If ' Assign auxilliary parameters required for the search. Console.WriteLine(("Searching " + uriString + " .......")) ' Attach QueryString to the WebClient. myWebClient.QueryString = myQueryStringCollection ' Download the search results Web page into 'searchresult.htm' for inspection. myWebClient.DownloadFile(uriString, "searchresult.htm") Console.WriteLine((ControlChars.Cr + "Download of " + uriString + " was successful. Please see 'searchresult.htm' for results."))
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.