js 判断字符串的结尾的字符串

 1 function confirmEnding(str, target) {
 2   // 请把你的代码写在这里
 3   var start = str.length-target.length;
 4   var arr = str.substr(start,target.length);
 5   if(arr == target){
 6     return true;
 7   }
 8  return false;
 9 }
10 
11 confirmEnding("He has to give me a new name", "name");