how to check if there are duplicates of an object javascript code example

Example 1: how to find duplicate item in array of object in javascript

const values = [
  { name: 'someName1' },
  { name: 'someName2' },
  { name: 'someName3' },
  { name: 'someName1' }
]

const uniqueValues = new Set(values.map(v => v.name));

if (uniqueValues.size < values.length) {
  console.log('uniqueValues')
}

Example 2: array of objects how to check if property has duplicate

var yourArray = [

{Index: 1, Name: "Farley, Charley", EmployeeCode: "12", PaymentType: "Void", CheckDate: "01/04/2012"},
{Index: 2, Name: "Farley, Charley", EmployeeCode: "12", PaymentType: "Void", CheckDate: "01/04/2012"},
{Index: 3, Name: "Tarley, Charley", EmployeeCode: "12", PaymentType: "Void", CheckDate: "01/04/2012"}
];

   unique = [...new Set(yourArray.map(propYoureChecking => propYoureChecking.Name))];
if (unique.length === 1) {
console.log(unique);
}

Example 3: js check if array of objects contains duplicates

const arrayOfObjCopy = [...arrayOfObj];

Object.keys(arrayOfObjCopy).forEach((key) => {
  arrayOfObjCopy[key] = JSON.stringify(arrayOfObjCopy[key]);
 });

const arrayOfObjhasDuplicates = uniq(arrayOfObjCopy).length != arrayOfObjCopy.length;