const names = ['John', 'Paul', 'George', 'Ringo', 'John'];
let unique = [...new Set(names)];
console.log(unique); // 'John', 'Paul', 'George', 'Ringo'array1 = array1.filter(function(val) {
return array2.indexOf(val) == -1;
});
// Or, with the availability of ES6:
array1 = array1.filter(val => !array2.includes(val));
uniqueArray = a.filter(function(item, pos) {
return a.indexOf(item) == pos;
})
array1 = array1.filter(function(val) {
return array2.indexOf(val) == -1;
});var car = ["Saab","Volvo","BMW","Saab","BMW",];
var cars = [...new Set(car)]
document.getElementById("demo").innerHTML = cars;function uniqByKeepFirst(a, key) {
let seen = new Set();
return a.filter(item => {
let k = key(item);
return seen.has(k) ? false : seen.add(k);
});
}
function uniqByKeepLast(a, key) {
return [
...new Map(
a.map(x => [key(x), x])
).values()
]
}
//
data = [
{a:1, u:1},
{a:2, u:2},
{a:3, u:3},
{a:4, u:1},
{a:5, u:2},
{a:6, u:3},
];
console.log(uniqByKeepFirst(data, it => it.u))
console.log(uniqByKeepLast(data, it => it.u))