对thg435的优秀答案稍作修改，以使用自定义比较器：

function contains(array, obj) {
    for (var i = 0; i < array.length; i++) {
        if (isEqual(array[i], obj)) return true;
    }
    return false;
}
//comparator
function isEqual(obj1, obj2) {
    if (obj1.name == obj2.name) return true;
    return false;
}
function removeDuplicates(ary) {
    var arr = [];
    return ary.filter(function(x) {
        return !contains(arr, x) && arr.push(x);
    });
}

VanillaJS：使用像Set这样的Object删除重复项

您可以始终尝试将其放入对象中，然后遍历其关键点：

function remove_duplicates(arr) {
    var obj = {};
    var ret_arr = [];
    for (var i = 0; i < arr.length; i++) {
        obj[arr[i]] = true;
    }
    for (var key in obj) {
        ret_arr.push(key);
    }
    return ret_arr;
}

Vanilla JS：通过跟踪已经看到的值来删除重复项（订单安全）

或者，对于订单安全版本，使用一个对象来存储所有以前看到的值，并在添加到数组之前检查值。

function remove_duplicates_safe(arr) {
    var seen = {};
    var ret_arr = [];
    for (var i = 0; i < arr.length; i++) {
        if (!(arr[i] in seen)) {
            ret_arr.push(arr[i]);
            seen[arr[i]] = true;
        }
    }
    return ret_arr;

}

ECMAScript 6：使用新的Set数据结构（顺序安全）

ECMAScript 6添加了新的Set Data Structure，它允许您存储任何类型的值。Set.values按插入顺序返回元素。

function remove_duplicates_es6(arr) {
    let s = new Set(arr);
    let it = s.values();
    return Array.from(it);
}

示例用法：

a = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"];

b = remove_duplicates(a);
// b:
// ["Adam", "Carl", "Jenny", "Matt", "Mike", "Nancy"]

c = remove_duplicates_safe(a);
// c:
// ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Carl"]

d = remove_duplicates_es6(a);
// d:
// ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Carl"]

这里是另一种使用jQuery的方法，

function uniqueArray(array){
  if ($.isArray(array)){
    var dupes = {}; var len, i;
    for (i=0,len=array.length;i<len;i++){
      var test = array[i].toString();
      if (dupes[test]) { array.splice(i,1); len--; i--; } else { dupes[test] = true; }
    }
  } 
  else {
    if (window.console) console.log('Not passing an array to uniqueArray, returning whatever you sent it - not filtered!');
      return(array);
  }
  return(array);
}

作者：William Skidmore

删除重复项的最简单方法是执行for循环，比较不同的元素并将它们推入新数组

 var array = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"];

 var removeDublicate = function(arr){
 var result = []
 var sort_arr = arr.sort() //=> optional
 for (var i = 0; i < arr.length; i++) {
        if(arr[ i + 1] !== arr[i] ){
            result.push(arr[i])
        }
 };
  return result
}  
console.log(removeDublicate(array))
==>  ["Adam", "Carl", "Jenny", "Matt", "Mike", "Nancy"]

以下脚本返回仅包含唯一值的新数组。它适用于字符串和数字。不需要额外的库，只需要普通的JS。

浏览器支持：

Feature Chrome  Firefox (Gecko)     Internet Explorer   Opera   Safari
Basic support   (Yes)   1.5 (1.8)   9                   (Yes)   (Yes)

https://jsfiddle.net/fzmcgcxv/3/

var duplicates = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl","Mike","Mike","Nancy","Carl"]; 
var unique = duplicates.filter(function(elem, pos) {
    return duplicates.indexOf(elem) == pos;
  }); 
alert(unique);

因此，选项如下：

let a = [11,22,11,22];
let b = []


b = [ ...new Set(a) ];     
// b = [11, 22]

b = Array.from( new Set(a))   
// b = [11, 22]

b = a.filter((val,i)=>{
  return a.indexOf(val)==i
})                        
// b = [11, 22]