js数组的包含方法

 if (typeof Array.indexOf !== 'function') {
     Array.prototype.indexOf = function (args) {
         var index = -1;
         for (var i = 0, l = this.length; i < l; i++) {
              if (this[i] === args) {
                  index = i;
                  break;
              }
         }
         return index;
     };
}

数组.indexOf(查找字符) >= 0