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
如果没有结果，可以使用jQuery grep和push: http://api.jquery.com/jQuery.grep/
这基本上是与“扩展原型”解决方案相同的解决方案，但没有扩展(或污染)原型。
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')
如果你需要一些简单的东西，而不想扩展数组原型:
// Example array
var array = [{id: 1}, {id: 2}, {id: 3}];
function pushIfNew(obj) {
for (var i = 0; i < array.length; i++) {
if (array[i].id === obj.id) { // modify whatever property you need
return;
}
}
array.push(obj);
}
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)
当你希望通过对象的特定属性进行搜索时，我使用了map和reduce来做到这一点，因为直接进行对象相等通常会失败。
var newItem = {'unique_id': 123};
var searchList = [{'unique_id' : 123}, {'unique_id' : 456}];
hasDuplicate = searchList
.map(function(e){return e.unique_id== newItem.unique_id})
.reduce(function(pre, cur) {return pre || cur});
if (hasDuplicate) {
searchList.push(newItem);
} else {
console.log("Duplicate Item");
}
