/**
 * 动态创建css标签
 * @example <link href="example.css" type="text/css" rel="stylesheet" media="all" />
 * @param href css文件地址
 * @param media
 * @param rel
 * @param type
 * @author keluo <pycorvn@yeah.net>
 */
function addStylesheet(href, media, rel, type) {
	var link = document.createElement('link');
	link.rel = rel || 'stylesheet';
	link.type = type || 'text/css';
	link.media = media || 'all';
	link.href = href;
	document.getElementsByTagName('head')[0].appendChild(link);
	link = null;
}

/**
 * 定位到指定url
 * @param url url地址
 * @author keluo <pycorvn@yeah.net>
*/
function navigateTo(url) {
	window.location.href = url;
}

/**
 * 创建XMLHttpRequest对象
 * @return obj
 */
function initAjax() {
    var Ajax = false;
    try {
        Ajax = new ActiveXObject('Msxml2.XMLHTTP');
    } catch(e) {
        try {
            Ajax = new ActiveXObject('Microsoft.XMLHTTP');
        }catch(e) {
            Ajax = false;
        }
    }
    if(!Ajax && typeof XMLHttpRequest != 'undefined') {
        Ajax = new XMLHttpRequest();
    }
    return Ajax;
}

/**
 * 处理从服务器端返回的响应信息
 * @param urlToCall 要请求的url
 * @param string functionToCallBack 返回处理函数名
 */
function getText(urlToCall, functionToCallBack)
{ 
	var Ajax = initAjax();
	if(Ajax) {
		Ajax.open("GET", urlToCall, true); 
		Ajax.onreadystatechange = function() { 
			if (Ajax.readyState == 4 && Ajax.status == 200) { 
				functionToCallBack(Ajax.responseText); 
				delete Ajax;
				Ajax = null;
			}
		}
		Ajax.send(null); 
	}
}

/**
 * 去除字符串左右空白
 * @param string str 需要处理的字符串
 * @return string
 */
function trim(str) {
	return str.replace(/(^\s*)|(\s*$)/g, '');
}

function isCnWord(str) {
	var reg=/^[\u4e00-\u9fa5](\s*[\u4e00-\u9fa5])*$/;
	return reg.test(str);
}