How to use JS to merge multiple arrays for recalculation-JS Tutorial-php.cn

How to use JS to merge multiple arrays for recalculation

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Release： 2018-05-25 13:54:38

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This time I will show you how to use JS to merge multiple arrays for recalculation, and how to use JS to merge multiple arrays for recalculation. What are the things to note?The following is a practical case, let’s take a look together take a look.

The example in this article describes the deduplication algorithm for merging multiple arrays implemented in JS. Share it with everyone for your reference, the details are as follows:

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;i++){
    arr.indexOf(arr2[i]) === -1 ? arr.push(arr2[i]) : 0;
  }
  return arr;
}
console.log(concat_(arr1,arr2));

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Running results:

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 <= 1){
    return false;
  }
  var concat_ = function(arr1,arr2){
    var arr = arr1.concat();
    for(var i=0;i<arr2.length;i++){
      arr.indexOf(arr2[i]) === -1 ? arr.push(arr2[i]) : 0;
    }
    return arr;
  }
  var result = concat_(arr1,arr2);
  for(var i=2;i<arguments.length;i++){
    result = concat_(result,arguments[i]);
  }
  return result;
}
console.log(concat(arr1,arr2,arr3));

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Running results:

//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 <= 1){
    return false;
  }
  var concat_ = function(arr1,arr2){
    var arr = arr1.concat();
    for(var i=0;i<arr2.length;i++){
      arr.indexOf(arr2[i]) === -1 ? arr.push(arr2[i]) : 0;
    }
    return arr;
  }
  var result = concat_(arr1,arr2);
  for(var i=2;i<arguments.length;i++){
    result = concat_(result,arguments[i]);
  }
  //排序
  function sortNumber(a,b){
    return a - b;
  }
  return result.sort(sortNumber);
}
console.log(concat(arr1,arr2,arr3));

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Run results:

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!