推送键值对以映射对象javascript

Question

I have the following object

     {
     "timetable": {
         "MONDAY": {
             "start-end0": {},
             "start-end1": {},
             "start-end2": {},
             "start-end3": {},
             "start-end4": {}
         }
     }

i need to add "start-end5" to MONDAY . I tried to use dot operator to monday like timetable.monday.start-end5={} it says monday undefined

Answer 1

• monday is not MONDAY
• Since start-end4 is not a valid identifier, obj.timetable.MONDAY.start-end5 = {} will not compile; you need to use the bracket syntax.

Thus,

obj.timetable.MONDAY["start-end5"] = {};

Answer 2

Variable name should be followed this restrictions

• Blanks & Commas are not allowed.
• No Special Symbols other than underscore(_) are allowed.
• First Character should be alphabet or Underscore.

Try like this

var time = {
  "timetable": {
    "MONDAY": {
      "start-end0": {},
      "start-end1": {},
      "start-end2": {},
      "start-end3": {},
      "start-end4": {}
    }
  }
}

time.timetable.MONDAY["start-end5"] = {}

DEMO

Addtion:

how can i add dynamically start-end5 start-end6... to my map??Is that possible?

Ans

Add a loop and concat string according to value.

Like this

var time = {
  "timetable": {
    "MONDAY": {
      "start-end0": {},
      "start-end1": {},
      "start-end2": {},
      "start-end3": {},
      "start-end4": {}
    }
  }
}
for(var i=0;i<5;i++) // set the limit of loop according to your need
  time.timetable.MONDAY["start-end"+i] = {}

DEMO

Answer 3

您需要在此处使用[""]表示法，因为您的键名不是camelCase或其他有效的对象键名

a.timetable.MONDAY["start-end5"] = {};

Answer 4

我想添加一种更可行（且易读）的语法，只是为了好玩：

time["timetable"]["MONDAY"]["start-end5"] = {};