javaScript常用工具库

//判断元素是否包含某个类
function hasClass(element, className,tagName) {
var oldClass = element.className;
if (!oldClass) {
return false;
}
var oldClassArr = oldClass.split(/\s+/);
for (var i = 0, len = oldClass.length; i < len; i++) {
if (oldClassArr[i] === className) {
return true;
}
}
return false;
}

//为元素增添一个新样式类
function addClass(element, newClassName) {
if (hasClass(newClassName)) {
return;
}

element.className = element.className ? [element.className, newClassName].join(' ') : newClassName;
}

//根据类名进行查找
function getElementByClassName(oElem, className) {
var result = [];
var condiArr = oElem.getElementsByTagName('*');
var reg = new RegExp('\\s+' + className + '\\s+');
for (var i = 0; i < condiArr.length; i++) {
if (reg.test(' ' + condiArr[i].className + ' ')) {
result.push(condiArr[i]);
}
}
return result;
}