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post() method

setTimeout(function () {

fnCallback(httpGet(sURL));

}, 10);

} else {

alert(“Your browser doesn’t support HTTP requests.”);

}

};

With this completed, it’s now possible to send a GET request using common code in a variety of

browsers:

var sURL = “http://www.somewhere.com/page.php”;

sURL = addURLParam(sURL, “name”, “Nicholas”);

sURL = addURLParam(sURL, “book”, “Professional JavaScript”);

Http.get(sURL, function(sData) {

alert(“Server sent back: “ + sData);

});

Remember, because LiveConnect requires you to enter the full URL for the request, you must always

supply the full URL with the

Http.get()

method, just in case the browser uses LiveConnect.

The post() method

The

post()

method works similarly to the

get()

method, except it needs three arguments: the URL, the

parameters string, and the callback function. For simplicity’s sake, a callback function for

post()

uses

the same format as the one used for

get()

The method itself is also remarkably similar to

get()

, using the same

if..else

statements. The only

differences are the setting of the request header, the number of arguments, and the fact that the method

sends a POST request instead of a GET. Here’s the method:

Http.post = function (sURL, sParams, fnCallback) {

if (bXmlHttpSupport) {

var oRequest = new XMLHttpRequest();

oRequest.open(“post”, sURL, true);

oRequest.setRequestHeader(“Content-Type”,

“application/x-www-form-urlencoded”);

oRequest.onreadystatechange = function () {

if (oRequest.readyState == 4) {

fnCallback(oRequest.responseText);

}

oRequest.send(sParams);

} else if (navigator.javaEnabled() && typeof java != “undefined”

&& typeof java.net != “undefined”) {

setTimeout(function () {

fnCallback(httpPost(sURL, sParams));

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Client-Server Communication

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