JavaScript检测数组重复元素的两种实现方式

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title>Title</title>
</head>
<body>
<input type="text" id="Values" style="width: 100px;height: 25px;">
<button id="gain">获取</button>
<!--gain-->
</body>
<script src="jquery-2.2.2.min.js"></script>
<script type="text/javascript">
 //方法一
var arr1 = ["11", "22", "33", "44"];
 var arr=new Array(arr1);
 Array.prototype.in_array=function(e){
 var r=new RegExp(','+e+',');
 return (r.test(','+this.join(this.S)+','));
 };
 $("#gain").on("click",function () {
 var newValue=$("#Values").val();
 console.log(newValue);
 if(arr.in_array(newValue)){
 alert("已重复，请不要重复添加");
 }else {
 arr1.push(newValue);
 console.log(arr1);
 }
 })
 //方法二
function isArr(arr,value) {
 for(var i=0;i<arr.length;i++){
 if(value===arr[i]){
 return true;
 }
 }
 return false;
 }
 var arr2 = ["11", "22", "33", "44"];//用于进行比较的数组
$("#gain").on("click",function () {
 var value2=$("#Values").val();
 if(isArr(arr2,value2)){
 alert("已重复，请不要重复添加")
 }else {
 arr2.push(value2);
 console.log(arr2);
 }
 })
</script>
</html>