Question

我在删除数组的第一个元素时遇到麻烦如果我尝试切片（1,1）或移位我无法得到一个列表。

例如，

我的数组：[1499783769720,"54:52:00:62:46:66","54:52:00:b0:fa:57","54:52:00:8f:d9:7c","54:52:00:e7:67:10","54:52:00:26:56:56","54:52:00:33:3a:4d","54:52:00:7b:f4:ec","54:52:00:1d:48:1e","54:52:00:55:14:ed","54:52:00:78:b8:51"]

我想删除时间戳“1499783769720”并且只有["54:52:00:62:46:66","54:52:00:b0:fa:57","54:52:00:8f:d9:7c","54:52:00:e7:67:10","54:52:00:26:56:56","54:52:00:33:3a:4d","54:52:00:7b:f4:ec","54:52:00:1d:48:1e","54:52:00:55:14:ed","54:52:00:78:b8:51"]

如果我尝试切片，我只获得一个值"54:52:00:78:b8:51"并且通过筛选得到1499783769720。

我怎么能这样做？

var randomMac = require('random-mac');
var now = Date.now();
var lista=[];

lista.push(now);
for(var i=0;i<10;i++){
    var random = randomMac();
    lista[i+1] = random;
}

Answer 1

您可以使用Array.prototype.shift()：shift（）方法从数组中删除第一个元素并返回该元素。此方法更改数组的长度。

var list = [1499783769720,"54:52:00:62:46:66","54:52:00:b0:fa:57","54:52:00:8f:d9:7c","54:52:00:e7:67:10","54:52:00:26:56:56","54:52:00:33:3a:4d","54:52:00:7b:f4:ec","54:52:00:1d:48:1e","54:52:00:55:14:ed","54:52:00:78:b8:51"];

list.shift(); // First removed
console.log(list);

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Answer 2

尝试理解这个例子：

var list = ["a","b","c","d"]
list = list.slice(1);
console.log(list);

切片函数不会更改原始数组，因此您需要重新分配数组变量。

Answer 3

尝试.slice(1)：

const firstRemoved = [
  1499783769720,
  '54:52:00:62:46:66',
  '54:52:00:b0:fa:57',
  '54:52:00:8f:d9:7c',
  '54:52:00:e7:67:10',
  '54:52:00:26:56:56',
  '54:52:00:33:3a:4d',
  '54:52:00:7b:f4:ec',
  '54:52:00:1d:48:1e',
  '54:52:00:55:14:ed',
  '54:52:00:78:b8:51'
].slice(1);

console.log(firstRemoved);

Answer 4

myArray.splice(myArray.indexOf(myArray[0]),1);

试试这个。 plnkr：plnkr.co/edit/tFEbwbFEyVX6TarlZJ2d?p=preview 使用这种方法，您可以传递确切的值并完全删除您需要的内容。

删除第一个元素数组Javascript Node.Js

4 个答案: