如果两个值都不存在,我如何推入数组?这是我的数组:

[
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" }
]

如果我试图再次推入数组的名字:“tom”或文本:“tasty”,我不希望发生任何事情…但如果这两个都不存在那么我就输入。push()

我该怎么做呢?


当前回答

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'}];

其他回答

如果你的项目包含lodash,使用unionBy方法会很简单

import {unionBy} from "lodash";

let arrayObj = [
    { name: "jhon", text: "guitar"},
    { name: "paul", text: "bass" },
    { name: "george", text: "guitar" }
];

// this object will be added to the array
arrayObj = unionBy(arrayObj, [{name: 'ringo', text: 'drums'}], 'name')

// this object will be ignored because already exists  
arrayObj = unionBy(arrayObj, [{name: "jhon", text: "guitar"}], 'name')

这里你有一种方法可以在一行中为两个数组做这件事:

const startArray = [1,2,3,4]
const newArray = [4,5,6]

const result = [...startArray, ...newArray.filter(a => !startArray.includes(a))]

console.log(result);
//Result: [1,2,3,4,5,6]

正是出于这些原因,使用像underscore.js这样的js库。union:计算传入数组的并集:在一个或多个数组中出现的唯一项的列表。

_.union([1, 2, 3], [101, 2, 1, 10], [2, 1]);
=> [1, 2, 3, 101, 10]

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)

http://api.jquery.com/jQuery.unique/

var cleanArray = $.unique(clutteredArray);

你可能对makeArray也感兴趣

前面的例子最好说明在push之前检查它是否存在。 事后看来,它还声明你可以将它声明为原型的一部分(我猜这是又名类扩展),所以下面没有大的增强。

除了我不确定indexOf是一个更快的路径,然后inArray?可能。

Array.prototype.pushUnique = function (item){
    if(this.indexOf(item) == -1) {
    //if(jQuery.inArray(item, this) == -1) {
        this.push(item);
        return true;
    }
    return false;
}