Sys.Net.WebRequest (Clase)
Actualización: noviembre 2007
Proporciona la funcionalidad de script de cliente para realizar una solicitud web.
Espacio de nombres:Sys.Net
Hereda: nada
var wRequest = new Sys.Net.WebRequest();
Constructores
Name |
Description |
|---|---|
Inicializa una nueva instancia de la clase WebRequest. |
Members
Name |
Description |
|---|---|
Registra un controlador de eventos al que se asocia la instancia de solicitud web. |
|
Provoca el evento completado para la instancia de Sys.Net.WebRequest asociada. |
|
Obtiene la dirección URL resuelta de la instancia de solicitud web. |
|
Emite una llamada de red para la instancia de solicitud web. |
|
Quita el controlador de eventos asociado a la instancia de solicitud web. |
|
Obtiene o establece el cuerpo HTTP de la solicitud web. |
|
Obtiene o establece el elemento de ejecución de la instancia de solicitud web asociada. |
|
Obtiene los encabezados HTTP de la solicitud web. |
|
Obtiene o establece el verbo HTTP de la solicitud web utilizado para emitir la solicitud web. |
|
Obtiene o establece el valor de tiempo de espera de la instancia de solicitud web. |
|
Obtiene o establece la dirección URL de la instancia de solicitud web. |
|
Obtiene o establece el contexto del usuario asociado a la instancia de solicitud web. |
Comentarios
La clase WebRequest la utilizan las clases de nivel de comunicación asincrónica para realizar una solicitud web. Normalmente, este tipo no se utiliza directamente en las aplicaciones. En lugar de ello, se llama a los métodos de servicio web o a los métodos de página estática desde el explorador mediante métodos de proxy. Para obtener más información, consulte Exponer servicios web a script de cliente.
Sin embargo, puede crear y utilizar una instancia de WebRequest en los casos siguientes:
Cuando desee realizar solicitudes de red que no sean llamadas simples a métodos de servicio web.
Cuando desee establecer directamente propiedades de solicitud HTTP.
Cuando utilice un elemento de ejecución personalizado basado en la clase Sys.Net.WebRequestExecutor.
Ejemplo
En el siguiente ejemplo se muestra cómo crear una instancia de la clase WebRequest para realizar una solicitud web GET. En el ejemplo se muestra una página web y el script de cliente utilizado para interactuar con la clase WebRequest.
<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title> Using WebRequest </title>
<style type="text/css">
body { font: 11pt Trebuchet MS;
font-color: #000000;
padding-top: 72px;
text-align: center }
.text { font: 8pt Trebuchet MS }
</style>
</head>
<body>
<h2>Using WebRequest</h2>
<form id="form1" runat="server">
<asp:ScriptManager runat="server" ID="ScriptManagerId">
<Scripts>
<asp:ScriptReference Path="WebRequest.js" />
</Scripts>
</asp:ScriptManager>
</form>
<table>
<tr align="left">
<td>Make GET Request:</td>
<td>
<button id="Button1"
onclick="GetWebRequest()">GET</button>
</td>
</tr>
<tr align="left">
<td>Request Body:</td>
<td>
<button id="Button2"
onclick="PostWebRequest()">Body</button>
</td>
</tr>
<tr align="left">
<td>Request Timeout:</td>
<td>
<button id="Button3"
onclick="WebRequestTimeout()">Timeout</button>
</td>
</tr>
<tr align="left">
<td>Request Completed Handler:</td>
<td>
<button id="Button4"
onclick="WebRequestCompleted()">Completed Handler</button>
</td>
</tr>
<tr align="left">
<td>Resolved Url:</td>
<td>
<button id="Button5"
onclick="GetWebRequestResolvedUrl()">Resolved Url</button>
</td>
</tr>
<tr align="left">
<td>Request Executor:</td>
<td>
<button id="Button6"
onclick="WebRequestExecutor()">Executor</button>
</td>
</tr>
<tr align="left">
<td>Request Header:</td>
<td>
<button id="Button7"
onclick="WebRequestHeader()">Header</button>
</td>
</tr>
</table>
<hr />
<div id="ResultId" style="background-color:Aqua;"></div>
</body>
</html>
<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title> Using WebRequest </title>
<style type="text/css">
body { font: 11pt Trebuchet MS;
font-color: #000000;
padding-top: 72px;
text-align: center }
.text { font: 8pt Trebuchet MS }
</style>
</head>
<body>
<h2>Using WebRequest</h2>
<form id="form1" runat="server">
<asp:ScriptManager runat="server" ID="ScriptManagerId">
<Scripts>
<asp:ScriptReference Path="WebRequest.js" />
</Scripts>
</asp:ScriptManager>
</form>
<table>
<tr align="left">
<td>Make GET Request:</td>
<td>
<button id="Button1"
onclick="GetWebRequest()">GET</button>
</td>
</tr>
<tr align="left">
<td>Request Body:</td>
<td>
<button id="Button2"
onclick="PostWebRequest()">Body</button>
</td>
</tr>
<tr align="left">
<td>Request Timeout:</td>
<td>
<button id="Button3"
onclick="WebRequestTimeout()">Timeout</button>
</td>
</tr>
<tr align="left">
<td>Request Completed Handler:</td>
<td>
<button id="Button4"
onclick="WebRequestCompleted()">Completed Handler</button>
</td>
</tr>
<tr align="left">
<td>Resolved Url:</td>
<td>
<button id="Button5"
onclick="GetWebRequestResolvedUrl()">Resolved Url</button>
</td>
</tr>
<tr align="left">
<td>Request Executor:</td>
<td>
<button id="Button6"
onclick="WebRequestExecutor()">Executor</button>
</td>
</tr>
<tr align="left">
<td>Request Header:</td>
<td>
<button id="Button7"
onclick="WebRequestHeader()">Header</button>
</td>
</tr>
</table>
<hr />
<div id="ResultId" style="background-color:Aqua;"></div>
</body>
</html>
var getPage;
var postPage;
var displayElement;
function pageLoad()
{
getPage = "getTarget.htm";
postPage = "postTarget.aspx";
displayElement = $get("ResultId");
}
// This function performs a GET Web request
// to retrieve information from the Url specified in
// the query string.
function GetWebRequest()
{
alert("Performing Get Web request.");
// Instantiate the WebRequest object.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(getPage);
// Set the request verb.
wRequest.set_httpVerb("GET");
// Set user's context
wRequest.set_userContext("user's context");
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompleted);
// Clear the results page element.
displayElement.innerHTML = "";
// Execute the request.
wRequest.invoke();
}
// This function performs a POST Web request
// to upload information to the resource
// identified by the Url.
function PostWebRequest()
{
// Instantiate the WebRequest object.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(postPage);
// Set the request verb.
wRequest.set_httpVerb("POST");
var body = "Message=Hello! Do you hear me?"
wRequest.set_body(body);
wRequest.get_headers()["Content-Length"] = body.length;
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompleted);
// Clear the results page element.
displayElement.innerHTML = "";
// Execute the request.
wRequest.invoke();
}
// This function adds and removes the
// Web request completed event handler.
function WebRequestCompleted()
{
// Instantiate the WebRequest.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(getPage);
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompleted);
alert("Added Web request completed handler");
// Remove the web request completed event handler.
// Comment the following two lines if you want to
// use the handler.
wRequest.remove_completed(OnWebRequestCompleted);
alert("Removed handler; the Web request return is not processed.");
// Execute the request.
wRequest.invoke();
}
// This function gets the resolved Url
// of the Web request instance.
function GetWebRequestResolvedUrl()
{
// Instantiate the WebRequest.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(getPage);
// Get the web request completed event handler.
var resUrl = wRequest.getResolvedUrl();
alert("Resolved Url: " + resUrl);
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompleted);
// Execute the request.
wRequest.invoke();
}
// This function gets and sets the
// Web request time out.
function WebRequestTimeout()
{
// Instantiate the WebRequest.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(getPage);
var defaultTimeout =
wRequest.get_timeout();
// Set request timeout to 100 msec.
wRequest.set_timeout(100);
var newTimeout =
wRequest.get_timeout();
alert("Default timeout: " + defaultTimeout);
alert("New timeout: " + newTimeout);
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompleted);
// Execute the request.
wRequest.invoke();
}
// This function sets the Web request
// executor, replacing the default one.
function WebRequestExecutor()
{
// Instantiate the WebRequest.
var wRequest = new Sys.Net.WebRequest();
// Create the executor. In this case it is an
// XMLHttpExecutor, equivalent to the default
// executor. But, you can create a custom one.
var executor = new Sys.Net.XMLHttpExecutor();
// Set the executor, replacing the default one.
// In this case the executor is equivalent to the
// default one.
wRequest.set_executor(executor);
// Get the current executor
var executor =
wRequest.get_executor();
alert("Response availabe: " + executor.get_responseAvailable())
}
// This function sets an HTTP header for
// the Web request.
function WebRequestHeader()
{
// Instantiate the WebRequest object.
var wRequest = new Sys.Net.WebRequest();
// Set the request Url.
wRequest.set_url(postPage);
// Set the request verb.
wRequest.set_httpVerb("POST");
var body = "Message=Hello! Do you hear me?"
wRequest.set_body(body);
// Set the value of the HTTP header's "Content-Length".
wRequest.get_headers()["Content-Length"] = body.length;
// Set the web request completed event handler,
// for processing return data.
wRequest.add_completed(OnWebRequestCompletedHeader);
// Clear the results page element.
displayElement.innerHTML = "";
// Execute the request.
wRequest.invoke();
}
// This the handler for the Web request completed event
// that is used to display return data.
function OnWebRequestCompleted(executor, eventArgs)
{
if(executor.get_responseAvailable())
{
// Clear the previous results.
displayElement.innerHTML = "";
// Display Web request status.
DisplayWebRequestStatus(executor);
// Display Web request headers.
DisplayWebRequestHeaders(executor);
// Display Web request body.
DisplayWebRequestBody(executor);
}
else
{
if (executor.get_timedOut())
alert("Timed Out");
else
if (executor.get_aborted())
alert("Aborted");
}
}
// This the handler for the Web request completed event
// that is used to display header information.
function OnWebRequestCompletedHeader(executor, eventArgs)
{
if(executor.get_responseAvailable())
{
// Clear the previous results.
displayElement.innerHTML = "";
// Display Web request headers.
DisplayWebRequestHeaders(executor);
}
else
{
if (executor.get_timedOut())
alert("Timed Out");
else
if (executor.get_aborted())
alert("Aborted");
}
}
// This function is used to display the Web request status.
function DisplayWebRequestStatus(executor)
{
displayElement.innerHTML +=
"Status: [" +
executor.get_statusCode() + " " +
executor.get_statusText() + "]" + "<br/>"
}
// This function is used to display Web request HTTP headers.
function DisplayWebRequestHeaders(executor)
{
displayElement.innerHTML +=
"Headers: ";
displayElement.innerHTML +=
executor.getAllResponseHeaders() + "<br/>";
}
// This function is used to display the Web request body.
function DisplayWebRequestBody(executor)
{
displayElement.innerHTML +=
"Body: ";
if (document.all)
displayElement.innerText +=
executor.get_responseData();
else
// Firefox
displayElement.textContent +=
executor.get_responseData();
}
// This function is used to display the Web request message.
function DisplayInformation(message)
{
// Clear the previous results.
displayElement.innerHTML = "";
// Display information.
displayElement.innerHTML = "<br/>" + message;
}
if (typeof(Sys) !== "undefined") Sys.Application.notifyScriptLoaded();