【XMLHttpRequest】获取XMLHttpRequest

// 获取http请求
	function getXMLHttpRequest() {
		req = false;
		//本地XMLHttpRequest对象
		if (window.XMLHttpRequest) {
			try {
				req = new XMLHttpRequest();
			} catch (e) {
				req = false;
			}
			//IE/Windows ActiveX版本
		} else if (window.ActiveXObject) {
			try {
				req = new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
				try {
					req = new ActiveXObject("Microsoft.XMLHTTP");
				} catch (e) {
					req = false;
				}
			}
		}
		return req;
	}