如何删除对象中的take属性下限值?

你只需要比较一下 .val 属性:

 function removeDuplicates(originalArray, prop) {
   var newArray = [];
   var lookupObject = {};

   // Modified lines
   for (var i in originalArray) {
     let item = lookupObject[originalArray[i][prop]];
     if (!item || item.val > originalArray[i].val) {
       lookupObject[originalArray[i][prop]] = originalArray[i];
     }
   }

   for (i in lookupObject) {
     newArray.push(lookupObject[i]);
   }
   return newArray;
 }

 var arr = [{
   "id": 1,
   "val": 0
 }, {
   "id": 2,
   "val": 0
 }, {
   "id": 3,
   "val": 0
 }, {
   "id": 1,
   "val": 1
 }];
 var myNewArray = removeDuplicates(arr, 'id');
 console.log(myNewArray);

for ... in 用于遍历数组!

你可以检查一下原始数组是否存在;已在查找对象上,然后在已在查找值和循环中的当前值之间使用min()函数来设置该值。

function removeDuplicates(originalArray, prop) {
     var newArray = [];
     var lookupObject  = {};

     for(var i in originalArray) {
        if (originalArray[i][prop] in lookupObject) {
            lookupObject[originalArray[i][prop]] = Math.max(lookupObject[originalArray[i][prop]], originalArray[i])
        } else {
            lookupObject[originalArray[i][prop]] = originalArray[i];
        }

     }

     for(i in lookupObject) {
         newArray.push(lookupObject[i]);
     }
      return newArray;
 }

 var arr = [{"id": 1, "val": 0},{"id": 2, "val": 0},{"id": 3, "val": 0},{"id": 1, "val": 1}];
 var myNewArray = removeDuplicates(arr, 'id');
 console.log(myNewArray);