数组去重的几种方式

发表于

一：遍历数组去重

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function arrays(arr){
	 var list = [];
   arr.forEach((item)=>{
       if(!list[item]){
           list.push(item)
       }
   })
   return list
}
var a = [1,2,4,6,'erw','wee',1,2,3,4,4,4];
console.log(arrays(a))

二：对象键值对匹配去重

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function arrays(arr){
    var obj = {},list = [],v,type;
    arr.forEach((item,index)=>{
       type = typeof item;
       if(!obj[item]){
           obj[item] = type;
           list.push(item)
       }else if(obj[item].indexOf(type) < 0){
           obj[item].push(type);
           list.push(item)
       }
    })
    return list
}
var a = [1,2,4,6,'erw','wee',1,2,3,4,4,4];
console.log(arrays(a))

三：数组排序后判断相邻是否相等

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function arrays(arr){
    arr.sort();
    let l = arr.length;
    var array = [arr[0]];
    for(let i = 1; i < l, i++){
    	 if(arr[i] !== arr[i-1]){
          array.push(arr[i])
    	 }
    }
    return array;
}
var a = [1,2,4,6,'erw','wee',1,2,3,4,4,4];
console.log(arrays(a))

四：获取最右值放入新数组

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    function arrays(array){ 
var r = []; 
for(var i = 0, l = array.length; i < l; i++) { 
   for(var j = i + 1; j < l; j++) 
      if (array[i] === array[j]) j = ++i; 
      r.push(array[i]); 
 } 
 return r; 
 }
    var a = [1,2,4,6,'erw','wee',1,2,3,4,4,4];
    console.log(arrays(a))