JSFiddle - React, Tailwind, and code Playground

by Cyril Cherian

JavaScript

var myObject = [{
  "name": 'Tom',
  "city": 'Chicago',
  "GroupCode": '1'
}, {
  "name": 'Harry',
  "city": 'Wisconsin',
  "GroupCode": '1'
}, {
  "name": 'Rob',
  "city": 'Los Angeles',
  "GroupCode": '2'
}, {
  "name": 'Peter',
  "city": 'Seattle',
  "GroupCode": '2'
}, {
  "name": 'Dave',
  "city": 'New York',
  "GroupCode": '3'
}, {
  "name": 'Steve',
  "city": 'Boston',
  "GroupCode": '3'
}];
//store the first groupcode
var gc = myObject[0].GroupCode;
myObject.forEach(function(ob, index) {
  if (gc != ob.GroupCode) {
    gc = ob.GroupCode;
    //insert this object
    myObject.splice(index, 0, {
      "name": '--',
      "city": '--',
      "GroupCode": '--'
    });
  }

})
console.log(myObject)