json字符串查询是否存在某id

JSON字符串查询某ID是否存在

//JSON数据例子
var data = {
  "students": [
    {
      "id": 1001,"name": "Tom","age": 20
    },{
      "id": 1002,"name": "Amy","age": 22
    },{
      "id": 1003,"name": "John","age": 19
    }
  ]
}

//查询是否存在某ID的函数
function isExistId(data,id) {
  for (var i = 0; i