javascript count duplicates in array of objects code example
Example 1: count duplicates array js
uniqueCount = ["a","b","c","d","d","e","a","b","c","f","g","h","h","h","e","a"];
var count = {};
uniqueCount.forEach(function(i) { count[i] = (count[i]||0) + 1;});
console.log(count);
Example 2: counting duplicate values javascript
var counts = {};
your_array.forEach(function(x) { counts[x] = (counts[x] || 0)+1; });
Example 3: how to count duplicates in an array javascript
arr.reduce((b,c)=>((b[b.findIndex(d=>d.el===c)]||b[b.push({el:c,count:0})-1]).count++,b),[]);
Example 4: 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;
Example 5: find duplicates in an object array
npm i find-array-duplicates
import duplicates from 'find-array-duplicates'
const names = [
{ 'age': 36, 'name': 'Bob' },
{ 'age': 40, 'name': 'Harry' },
{ 'age': 1, 'name': 'Bob' }
]
duplicates(names, 'name').single()
// => [{ 'age': 36, 'name': 'Bob' }]