使用 JavaScript 从数组中删除对象

javascript arrays

2022-08-29 22:32:02

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

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"}];

答案 1

您可以使用多种方法从数组中删除项目：

//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

如果要删除位置处的元素，请使用：x

someArray.splice(x, 1);

或

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

回复@chill182的评论：您可以使用或组合（参见 MDN）从数组中删除一个或多个元素，例如Array.filterArray.spliceArray.findIndex

// 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>

答案 2

干净的解决方案是使用Array.filter：

var filtered = someArray.filter(function(el) { return el.Name != "Kristian"; });

这样做的问题是它不适用于IE <9。但是，您可以包含来自Javascript库的代码（例如下划线.js），该代码为任何浏览器实现此功能。