幾個常用的自訂js方法

/** * 判斷val是否為空白 * @param val * @returns */function isEmpty(val){if(val == '' || val == undefined || val == null){return true;}else{return false;}}/** * 判斷obj是否存在 * @param obj * @returns {Boolean} */function exists(obj){if (obj.length) {return true;}else{return false;}}/** * 判斷集合collection是否包含某元素element * @param collection * @param element * @returns */function seqContains(collection, element){ for (var i = 0; i < collection.length; i++) {         if (collection[i] == element) {             return true;         }     } return false;}/** * 遍曆js對象所有屬性 * @param obj * @returns {String} */function traverseObj(obj){var props = "";for(var p in obj){ if(typeof(obj[p])=="function"){     obj[p]();}else{     //-- p為屬性名稱，obj[p]為對應屬性的值    props+= p + "=" + obj[p] + "\n";} } return props;}