如何检查一个数组是否包含另一个数组? [英] How to check if an array contains another array?

问题描述

我需要二维数组，所以我做了一个嵌套数组，因为 JavaScript 不允许.

它们看起来像这样:

var myArray = [[1, 0],[1, 1],[1, 3],[2, 4]]

如何检查此数组是否包含 vanilla JS 中的特定元素(即这些 [0,1] 数组之一)?

这是我尝试过的，但没有成功(一切都返回 false)(我在代码段中包含了答案):

var myArray = [[1, 0],[1, 1],[1, 3],[2, 4]]var itemTrue = [2, 4];var itemFalse = [4, 4];函数包含(a，obj){var i = a.length;当我 - ) {如果(a[i] === obj){返回真；}}返回假；}//第一个答案的解决方案函数 isArrayInArray(x, 检查) {for (var i = 0, len = x.length; i < len; i++) {if (x[i][0] === check[0] && x[i][1] === check[1]) {返回真；}}返回假；}//接受答案的解决方案函数 isArrayInArray2(x, 检查) {var 结果 = x.find(function(ele) {返回 (JSON.stringify(ele) === JSON.stringify(check));})返回结果 !=null}console.log("true :" + myArray.includes(itemTrue));console.log("false :" + myArray.includes(itemFalse));console.log("true :" + (myArray.indexOf(itemTrue) != -1));console.log("false :" + (myArray.indexOf(itemFalse) != -1));console.log("true :" + contains(myArray, itemTrue));console.log("false :" + contains(myArray, itemFalse));//第一个答案的解决方案console.log("true :" + isArrayInArray(myArray, itemTrue));console.log("false :" + isArrayInArray(myArray, itemFalse));//接受答案的解决方案console.log("true :" + isArrayInArray2(myArray, itemTrue));console.log("false :" + isArrayInArray2(myArray, itemFalse));

它可能看起来像重复，但我找不到类似的问题.如果是，请随意标记它.

解决方案

简短易行，将数组字符串化并作为字符串进行比较

function isArrayInArray(arr, item){var item_as_string = JSON.stringify(item);var contains = arr.some(function(ele){返回 JSON.stringify(ele) === item_as_string;});返回包含；}var myArray = [[1, 0],[1, 1],[1, 3],[2, 4]]var item = [1, 0]console.log(isArrayInArray(myArray, item));//如果找到则打印真

检查一些文档这里

I needed 2d arrays, so I made a nested array since JavaScript doesn't allow them.

They look like this:

var myArray = [
  [1, 0],
  [1, 1],
  [1, 3],
  [2, 4]
]

How can I check if this array includes a specific element (i.e. one of these [0,1] arrays) in vanilla JS?

Here is what I tried, with no success (everything returns false) (EDIT: I included the answers in the snippet):

var myArray = [
  [1, 0],
  [1, 1],
  [1, 3],
  [2, 4]
]

var itemTrue = [2, 4];
var itemFalse = [4, 4];

function contains(a, obj) {
  var i = a.length;
  while (i--) {
    if (a[i] === obj) {
      return true;
    }
  }
  return false;
}

// EDIT: first answer's solution

function isArrayInArray(x, check) {
  for (var i = 0, len = x.length; i < len; i++) {
    if (x[i][0] === check[0] && x[i][1] === check[1]) {
      return true;
    }
  }
  return false;
}

// EDIT: accepted answer's solution


function isArrayInArray2(x, check) {
  var result = x.find(function(ele) {
    return (JSON.stringify(ele) === JSON.stringify(check));
  }) 
  return result !=null
}

console.log("true :" + myArray.includes(itemTrue));
console.log("false :" + myArray.includes(itemFalse));

console.log("true :" + (myArray.indexOf(itemTrue) != -1));
console.log("false :" + (myArray.indexOf(itemFalse) != -1));

console.log("true :" + contains(myArray, itemTrue));
console.log("false :" + contains(myArray, itemFalse));

// EDIT: first answer's solution
console.log("true :" + isArrayInArray(myArray, itemTrue));
console.log("false :" + isArrayInArray(myArray, itemFalse));


// EDIT: accepted answer's solution
console.log("true :" + isArrayInArray2(myArray, itemTrue));
console.log("false :" + isArrayInArray2(myArray, itemFalse));

It could look like duplicate but I couldn't find a similar question. If it is, feel free to tag it as such.

解决方案

Short and easy, stringify the array and compare as strings

function isArrayInArray(arr, item){
  var item_as_string = JSON.stringify(item);

  var contains = arr.some(function(ele){
    return JSON.stringify(ele) === item_as_string;
  });
  return contains;
}

var myArray = [
  [1, 0],
  [1, 1],
  [1, 3],
  [2, 4]
]
var item = [1, 0]

console.log(isArrayInArray(myArray, item));  // Print true if found

check some documentation here

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