xmlhttp.jsc

《JavaScript王者归来》examples.rar

# language: JSVM2

/**
 * @fileoverview js.net.XmlHttp class {@link http://jsvm.org/}
 * @file		XmlHttp.jsc
 * @author	Wan Changhua
 * @version	2.01, 10/23/05
 * @since		JSVM2.0
 */

package js.net;

import js.lang.NotSupportException;
import js.lang.System;

/**
 * Create a new XmlHttp instance.
 * Inherit from js.lang.JObject
 * @author	Wan Changhua
 * @version	2.01, 10/23/05
 * @extends JObject
 * @class This is the xmlhttp class.
 * @constructor
 * @throws NotSupportException if current browser does not support XmlHttp/XMLHttpRequest.
 * @return  a <code>XMLHttpRequest</code> instance if the current browser is moz.
 *          a <code>Microsoft.XMLHTTP</code> instance otherwise.
 */
class XmlHttp()
{
	this.init();
}

/**
 * @type XMLHttpRequest
 */
XmlHttp.prototype.getXMLHttpRequest = function ()
{
	return this.__request;
}

XmlHttp.prototype.init = function ()
{
	this.__request = XmlHttp.create();
}

XmlHttp.prototype.destroy = function ()
{
	this.__request = null;
}

/**
 * Retrieves a new XmlHttp instance.
 * @return  a <code>Microsoft.XMLHTTP</code> instance if the current browser is ie.
 *          a <code>XMLHttpRequest</code> instance otherwise.
 * @type XmlHttp
 */
XmlHttp.create = function ()
{
	if (!System.isIeBrowser())
	{
		return new XMLHttpRequest();
	}
	else
	{
		if (progId != null)
		{
			return new ActiveXObject(progId);
		}
		for (var i = 0; i < progIds.length; i++)
		{
			try
			{
				var obj = new ActiveXObject(progIds[i]);
				progId = progIds[i];
				return obj;
			}
			catch (ex) { }
			finally
			{
				obj = null;
			}
		}
	}
	throw new NotSupportException(XmlHttp.getName()
		+ ".create() error: can't create xmlhttp object ["
		+ System.getPlatform() + "].");
}

/**
 * @private
 */
var progIds = ["MSXML2.XMLHTTP", "Microsoft.XMLHTTP", "MSXML.XMLHTTP", "MSXML3.XMLHTTP"];
var progId = null;