//按指定位置删除
Array.prototype.removeIndex = function (index) {  if (index > - 1) {    this.splice(index, 1);  }};
//按元素名称删除Array.prototype.remove = function (val) {  var index = this.indexOf(val);  if (index > - 1) {    this.splice(index, 1);  }};
//添加元素到指定位置Array.prototype.add = function (val, index) {  if (index > - 1) {    this.splice(index, 0, val);  }};var temparr = new Array();//数组添加几条数据temparr.add(‘eavel‘, 0);temparr.add(‘vateal‘, 1);temparr.add(‘ftsva‘, 2);temparr.add(‘wevel‘, 3);console.log(temparr.toString());//输出"eavel,vateal,ftsva,wevel";//删除"vateal"操作temparr.remove(‘vateal‘);console.log(temparr.toString());//输出"eavel,ftsva,wevel";//在第二个位置添加一个新元素temparr.add(‘newvateal‘, 1);console.log(temparr.toString());//输出"eavel,newvateal,ftsva,wevel";//删除第二个位置的元素temparr.removeIndex(1);console.log(temparr.toString());//输出"eavel,ftsva,wevel";