How to remove duplicates when merging multiple arrays in JS

This time I will show you how to remove duplicates in JS when merging multiple arrays. What are the precautions for deduplication in JS when merging multiple arrays? The following is a practical case, let's take a look.

var arr1 = ['a','b'];
var arr2 = ['a','c','d'];
var arr3 = [1,'d',undefined,true,null];
//合并两个数组，去重
var concat_ = function(arr1,arr2){
  //不要直接使用var arr = arr1，这样arr只是arr1的一个引用，两者的修改会互相影响
  var arr = arr1.concat();
  //或者使用slice()复制，var arr = arr1.slice(0)
  for(var i=0;i<arr2.length console.log><p style="text-align: left;">Run result:</p>
<p style="text-align: left;"><img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/002/72c77a93407be5a7ba49a8f6fb852ef7-0.png?x-oss-process=image/resize,p_40" class="lazy" alt="">##</p>
<pre class="brush:php;toolbar:false">var arr1 = ['a','b'];
var arr2 = ['a','c','d'];
var arr3 = [1,'d',undefined,true,null];
//合并多个数组，去重
var concat = function(arr1,arr2,arr3){
  if(arguments.length Run result:<p style="text-align: left;"></p><p style="text-align: left;">##</p><pre class="brush:php;toolbar:false">//合并多个数组，去重，排序
var arr1 = [1,6,4,0];
var arr2 = [8,20,7,4.5];
var arr3 = [6,0,7,90,2];
var concat = function(arr1,arr2,arr3){
  if(arguments.length <img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/002/72c77a93407be5a7ba49a8f6fb852ef7-1.png?x-oss-process=image/resize,p_40" class="lazy" alt="">Run result:<p   style="max-width:90%"></p><p style="text-align: left;"><img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/002/140aa893eaf8d12417ab3a08a220ec62-2.png?x-oss-process=image/resize,p_40" class="lazy" alt=""> I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website! </p><p>Recommended reading: </p><p></p>React props and state attribute practical case explanation<p><a href="http://www.php.cn/js-tutorial-401916.html" target="_blank"></a><br></p>vue-simplemde to make image drag and drop, Paste <p><a href="http://www.php.cn/js-tutorial-401905.html" target="_blank"   style="max-width:90%"></a></p>

The above is the detailed content of How to remove duplicates when merging multiple arrays in JS. For more information, please follow other related articles on the PHP Chinese website!