xxxxxxxxxx
const checkObjectExist = (obj,list) => {
let i;
for (i = 0; i < list.length; i++) {
if (list[i] === obj) {
return true;
}
}
return false;
}
xxxxxxxxxx
const values = [{id: 10, name: 'someName1'}, {id: 10, name: 'someName2'}, {id: 11, name:'someName3'}, {id: 12, name: 'someName4'}];
const lookup = values.reduce((a, e) => {
a[e.id] = ++a[e.id] || 0;
return a;
}, {});
console.log(values.filter(e => lookup[e.id]));
Run code snippetHide results
xxxxxxxxxx
const arry = [1, 2, 1, 3, 4, 3, 5];
const toFindDuplicates = arry => arry.filter((item, index) => arr.indexOf(item) !== index)
const duplicateElementa = tofindDuplicates(arry);
console.log(duplicateElements);
// Output: [1, 3]
xxxxxxxxxx
const arrayOfObjCopy = [arrayOfObj];
Object.keys(arrayOfObjCopy).forEach((key) => {
arrayOfObjCopy[key] = JSON.stringify(arrayOfObjCopy[key]);
});
const arrayOfObjhasDuplicates = uniq(arrayOfObjCopy).length != arrayOfObjCopy.length;
xxxxxxxxxx
duplicateIds = arr
.map(e => e['id'])
.map((e, i, final) => final.indexOf(e) !== i && i)
.filter(obj=> arr[obj])
.map(e => arr[e]["id"])