如何从数组中删除对象? 我希望从someArray中删除包含名称Kristian的对象。例如:

someArray = [{name:"Kristian", lines:"2,5,10"},
             {name:"John", lines:"1,19,26,96"}];

我想实现:

someArray = [{name:"John", lines:"1,19,26,96"}];

当前回答

你可以使用array.filter()。

如。

        someArray = [{name:"Kristian", lines:"2,5,10"},
                     {name:"John", lines:"1,19,26,96"}];

        someArray = someArray.filter(function(returnableObjects){
               return returnableObjects.name !== 'Kristian';
        });

        //someArray will now be = [{name:"John", lines:"1,19,26,96"}];

箭头功能:

someArray = someArray.filter(x => x.name !== 'Kristian')

其他回答

这个答案

for (var i =0; i < someArray.length; i++)
   if (someArray[i].name === "Kristian") {
      someArray.splice(i,1);
   }

对于满足条件的多个记录不工作。如果您有两个这样的连续记录,则只删除第一个记录,跳过另一个记录。你必须使用:

for (var i = someArray.length - 1; i>= 0; i--)
   ...

代替。

你可以使用以下几种方法从数组中删除项:

//1
someArray.shift(); // first element removed
//2
someArray = someArray.slice(1); // first element removed
//3
someArray.splice(0, 1); // first element removed
//4
someArray.pop(); // last element removed
//5
someArray = someArray.slice(0, someArray.length - 1); // last element removed
//6
someArray.length = someArray.length - 1; // last element removed

如果你想移除x位置的元素,使用:

someArray.splice(x, 1);

Or

someArray = someArray.slice(0, x).concat(someArray.slice(-x));

回复@chill182的评论:您可以使用array从数组中删除一个或多个元素。过滤器或数组。拼接结合数组。findIndex(参见MDN)。

请看这个Stackblitz项目或下面的代码片段:

// non destructive filter > noJohn = John removed, but someArray will not change let someArray = getArray(); let noJohn = someArray.filter( el => el.name !== "John" ); log(`let noJohn = someArray.filter( el => el.name !== "John")`, `non destructive filter [noJohn] =`, format(noJohn)); log(`**someArray.length ${someArray.length}`); // destructive filter/reassign John removed > someArray2 = let someArray2 = getArray(); someArray2 = someArray2.filter( el => el.name !== "John" ); log("", `someArray2 = someArray2.filter( el => el.name !== "John" )`, `destructive filter/reassign John removed [someArray2] =`, format(someArray2)); log(`**someArray2.length after filter ${someArray2.length}`); // destructive splice /w findIndex Brian remains > someArray3 = let someArray3 = getArray(); someArray3.splice(someArray3.findIndex(v => v.name === "Kristian"), 1); someArray3.splice(someArray3.findIndex(v => v.name === "John"), 1); log("", `someArray3.splice(someArray3.findIndex(v => v.name === "Kristian"), 1),`, `destructive splice /w findIndex Brian remains [someArray3] =`, format(someArray3)); log(`**someArray3.length after splice ${someArray3.length}`); // if you're not sure about the contents of your array, // you should check the results of findIndex first let someArray4 = getArray(); const indx = someArray4.findIndex(v => v.name === "Michael"); someArray4.splice(indx, indx >= 0 ? 1 : 0); log("", `someArray4.splice(indx, indx >= 0 ? 1 : 0)`, `check findIndex result first [someArray4] = (nothing is removed)`, format(someArray4)); log(`**someArray4.length (should still be 3) ${someArray4.length}`); // -- helpers -- function format(obj) { return JSON.stringify(obj, null, " "); } function log(...txt) { document.querySelector("pre").textContent += `${txt.join("\n")}\n` } function getArray() { return [ {name: "Kristian", lines: "2,5,10"}, {name: "John", lines: "1,19,26,96"}, {name: "Brian", lines: "3,9,62,36"} ]; } <pre> **Results** </pre>

这是一个对我有用的函数:

function removeFromArray(array, value) {
    var idx = array.indexOf(value);
    if (idx !== -1) {
        array.splice(idx, 1);
    }
    return array;
}
someArray = jQuery.grep(someArray , function (value) {
        return value.name != 'Kristian';
});

性能

今天2021.01.27我在Chrome v88, Safari v13.1.2和Firefox v84上对所选解决方案的MacOs HighSierra 10.13.6进行测试。

结果

对于所有浏览器:

当元素不存在时,最快/最快的解决方案:A和B 快速/最快的大数组解决方案:C 当元素存在时,大数组的快速/最快解决方案:H 对于小数组来说是非常缓慢的解:F和G 对于大数组:D, E和F,非常缓慢的解决方案

细节

我执行4个测试用例:

小数组(10个元素)和元素存在-你可以在这里运行它 小数组(10个元素)和元素不存在-你可以在这里运行它 大数组(百万元素)和元素存在-你可以在这里运行它 大数组(百万元素)和元素不存在-你可以在这里运行它

下面的代码片段展示了解决方案之间的差异 一个 B C D E F G H 我

function A(arr, name) { let idx = arr.findIndex(o => o.name==name); if(idx>=0) arr.splice(idx, 1); return arr; } function B(arr, name) { let idx = arr.findIndex(o => o.name==name); return idx<0 ? arr : arr.slice(0,idx).concat(arr.slice(idx+1,arr.length)); } function C(arr, name) { let idx = arr.findIndex(o => o.name==name); delete arr[idx]; return arr; } function D(arr, name) { return arr.filter(el => el.name != name); } function E(arr, name) { let result = []; arr.forEach(o => o.name==name || result.push(o)); return result; } function F(arr, name) { return _.reject(arr, el => el.name == name); } function G(arr, name) { let o = arr.find(o => o.name==name); return _.without(arr,o); } function H(arr, name) { $.each(arr, function(i){ if(arr[i].name === 'Kristian') { arr.splice(i,1); return false; } }); return arr; } function I(arr, name) { return $.grep(arr,o => o.name!=name); } // Test let test1 = [ {name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}, ]; let test2 = [ {name:"John3", lines:"1,19,26,96"}, {name:"Kristian", lines:"2,5,10"}, {name:"John", lines:"1,19,26,96"}, {name:"Joh2", lines:"1,19,26,96"}, ]; let test3 = [ {name:"John3", lines:"1,19,26,96"}, {name:"John", lines:"1,19,26,96"}, {name:"Joh2", lines:"1,19,26,96"}, ]; console.log(` Test1: original array from question Test2: array with more data Test3: array without element which we want to delete `); [A,B,C,D,E,F,G,H,I].forEach(f=> console.log(` Test1 ${f.name}: ${JSON.stringify(f([...test1],"Kristian"))} Test2 ${f.name}: ${JSON.stringify(f([...test2],"Kristian"))} Test3 ${f.name}: ${JSON.stringify(f([...test3],"Kristian"))} `)); <script src="https://code.jquery.com/jquery-3.5.1.min.js" integrity="sha256-9/aliU8dGd2tb6OSsuzixeV4y/faTqgFtohetphbbj0=" crossorigin="anonymous"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.20/lodash.min.js" integrity="sha512-90vH1Z83AJY9DmlWa8WkjkV79yfS2n2Oxhsi2dZbIv0nC4E6m5AbH8Nh156kkM7JePmqD6tcZsfad1ueoaovww==" crossorigin="anonymous"> </script> This shippet only presents functions used in performance tests - it not perform tests itself!

这里是chrome的示例结果