这个问题有点老了，但我的选择是

    let finalTab = [{id: 1, name: 'dupont'}, {id: 2, name: 'tintin'}, {id: 3, name:'toto'}]; // Your array of object you want to populate with distinct data
    const tabToCompare = [{id: 1, name: 'dupont'}, {id: 4, name: 'tata'}]; // A array with 1 new data and 1 is contain into finalTab
    
    finalTab.push(
      ...tabToCompare.filter(
        tabToC => !finalTab.find(
          finalT => finalT.id === tabToC.id)
      )
    ); // Just filter the first array, and check if data into tabToCompare is not into finalTab, finally push the result of the filters

    console.log(finalTab); // Output : [{id: 1, name: 'dupont'}, {id: 2, name: 'tintin'}, {id: 3, name: 'toto'}, {id: 4, name: 'tata'}];

不确定速度，但stringification + indexOf是一个简单的方法。首先将数组转换为字符串:

let strMyArray = JSON.stringify(myArray);

然后，对于一系列属性-值对，您可以使用:

if (strMyArray.indexOf('"name":"tom"') === -1 && strMyArray.indexOf('"text":"tasty"') === -1) {
   myArray.push({ name: "tom", text: "tasty" });
}

查找整个对象更简单:

if (strMyArray.indexOf(JSON.stringify(objAddMe) === -1) { 
   myArray.push(objAddMe);
}

我有这个问题，我做了一个简单的原型，使用它，如果你喜欢它

Array.prototype.findOrPush = function(predicate, fallbackVal) {
    let item = this.find(predicate)
    if(!item){
        item = fallbackVal
        this.push(item)
    }
    return item
}

let arr = [{id: 1}]
let item = arr.findOrPush(e => e.id == 2, {id: 2})
console.log(item) // {id: 2} 

// will not push and just return existing value
arr.findOrPush(e => e.id == 2, {id: 2}) 
conslog.log(arr)  // [{id: 1}, {id: 2}]

对于字符串数组(但不是对象数组)，你可以通过调用.indexOf()来检查一个项是否存在，如果不存在，则将该项推入数组:

var newItem = "NEW_ITEM_TO_ARRAY"; var array = ["OLD_ITEM_1"， "OLD_ITEM_2"]; array.indexOf(newItem) === -1 ?array.push(newItem): console.log("此项已存在"); console.log(数组)

短的例子:

if (typeof(arr[key]) === "undefined") {
  arr.push(key);
}

推动动态

var a = [
  {name:"bull", text: "sour"},
  {name: "tom", text: "tasty" },
  {name: "Jerry", text: "tasty" }
]

function addItem(item) {
  var index = a.findIndex(x => x.name == item.name)
  if (index === -1) {
    a.push(item);
  }else {
    console.log("object already exists")
  }
}

var item = {name:"bull", text: "sour"};
addItem(item);

用简单的方法

var item = {name:"bull", text: "sour"};
a.findIndex(x => x.name == item.name) == -1 ? a.push(item) : console.log("object already exists")

如果数组只包含基元类型/简单数组

var b = [1, 7, 8, 4, 3];
var newItem = 6;
b.indexOf(newItem) === -1 && b.push(newItem);