WebClient.QueryString Eigenschaft

Definition

Namespace:

System.Net

Assembly:

System.Net.WebClient.dll

Quelle:

WebClient.cs

Ruft eine Auflistung der Name-Wert-Paare für Abfragen auf, die der Anforderung zugeordnet sind, oder legt diese fest.

public:
 property System::Collections::Specialized::NameValueCollection ^ QueryString { System::Collections::Specialized::NameValueCollection ^ get(); void set(System::Collections::Specialized::NameValueCollection ^ value); };

public System.Collections.Specialized.NameValueCollection QueryString { get; set; }

member this.QueryString : System.Collections.Specialized.NameValueCollection with get, set

Public Property QueryString As NameValueCollection

Eigenschaftswert

NameValueCollection

Eine NameValueCollection mit den der Anforderung zugeordneten Name-Wert-Paaren für Abfragen. Wenn der Anforderung keine Paare zugeordnet sind, ist der Wert eine leere NameValueCollection.

Beispiele

Im folgenden Codebeispiel werden Benutzereingaben aus der Befehlszeile verwendet und eine NameValueCollection erstellt, die der QueryString -Eigenschaft zugewiesen ist. Anschließend wird die Antwort vom Server in eine lokale Datei heruntergeladen.

String^ uriString = "http://www.contoso.com/search";
// Create a new WebClient instance.
WebClient^ myWebClient = gcnew WebClient;
// Create a new NameValueCollection instance to hold the QueryString parameters and values.
NameValueCollection^ myQueryStringCollection = gcnew NameValueCollection;
Console::Write( "Enter the word(s), separated by space character to search for in {0}: ", uriString );
// Read user input phrase to search for at uriString.
String^ searchPhrase = Console::ReadLine();
if ( searchPhrase->Length > 1 )
{
   // Assign the user-defined search phrase.
   myQueryStringCollection->Add( "q", searchPhrase );
}
else
{
   // If error, default to search for 'Microsoft'.
   myQueryStringCollection->Add( "q", "Microsoft" );
}
// Assign auxilliary parameters required for the search.
Console::WriteLine( "Searching {0} .......", 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( "\nDownload of {0} was successful. Please see 'searchresult.htm' for results.", uriString );

string uriString = "http://www.contoso.com/search";
// Create a new WebClient instance.
WebClient myWebClient = new WebClient();
// Create a new NameValueCollection instance to hold the QueryString parameters and values.
NameValueCollection myQueryStringCollection = new NameValueCollection();
Console.Write("Enter the word(s), separated by space character to search for in " +  uriString + ": ");
// Read user input phrase to search for at uriString.
string searchPhrase = Console.ReadLine();
if (searchPhrase.Length > 1)
    // Assign the user-defined search phrase.
    myQueryStringCollection.Add("q",searchPhrase);
else
    // If error, default to search for 'Microsoft'.
    myQueryStringCollection.Add("q","Microsoft");		
// 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("\nDownload of " + uriString + " was successful. Please see 'searchresult.htm' for results.");

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."))

Hinweise

Die QueryString -Eigenschaft enthält eine NameValueCollection instance, die Name-Wert-Paare enthält, die als Abfragezeichenfolge an den URI angefügt werden. Dem Inhalt der QueryString Eigenschaft wird ein Fragezeichen (?) vorangestellt, und Name-Wert-Paare werden durch ein ampersand (&) voneinander getrennt.