JS二分法查找数值在数值中的区间

 1 $(function(){
 2     //二分法计算最近的数组下标
 3     Array.prototype.binarySearch = function(obj){
 4         //var value = 0;
 5         var left = 0;
 6         var right = this.length;
 7         while(left <= right){
 8             var center = Math.floor((left+right)/2); 
 9             if(obj<this[center]){
10                 right = center - 1;
11             }else{
12                 left = center + 1;
13             }
14         }
15         return right;
16     }
17         //测试数据
18         var tempArray = new Array(‘0‘,‘10‘,‘20‘,‘30‘);
19         var obj = 18;
20         console(tempArray.binarySearch(obj));
21 });