JS将数组相同的元素进行分类

男娘i 2022-10-12 12:17 197阅读 0赞

### js实现将数组中相同元素进行分类，思路是先将数组去重，这里采用对象的方式进行去重，然后将相同的元素重新放入一个数组内,实例如下： ###

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>Document</title>
        <script>
        //普通数组
            var arr = [1,2,3,3,2,1,1,2,3];
            var obj = {};
            arr.forEach(item=>{
                obj[item] = item;
            });//利用对象去重
            console.log(obj);
            for(var o in obj){
                obj[o] = []
            }
            console.log(obj);
    		//上面两步可以简写为下面一个步骤
    		/*arr.forEach((item)=>{
    				obj[item] = [];
    		})*/
    		//将数组中相同的元素放入同一个数组
            arr.forEach(item=>{
                console.log(item);
                for(var o in obj){
                    if(item==o){
                    obj[o].push(item);
                }
                }  
            });
            console.log(obj);
    		//如果是比较复杂的数据，下面以数组对象为例，subId相同的分为一组
            var datas = JSON.parse(JSON.stringify({"datas": [{
    					"pId": "2211380240034753",
    					"subId": "-7629697887759678641",
    					"logType": "1",
    					"date": "2021-07-02"
    				}, {
    					"pId": "2211380240034753",
    					"subId": "-7629697887759678641",
    					"logType": "1",
    					"date": "2021-07-02"
    				}, {
    					"pId": "2211380240034753",
    					"subId": "278923639442458524",
    					"logType": "1",
    					"date": "2021-07-02"
    				}, {
    					"pId": "2211380240034753",
    					"subId": "278923639442458524",
    					"logType": "1",
    					"date": "2021-07-02"
    				}, {
    					"pId": "2211380240034753",
    					"subId": "278923639442458524",
    					"logType": "1",
    					"date": "2021-07-02"
    				}, {
    					"pId": "2211380240034753",
    					"subId": "-7629697887759678641",
    					"logType": "1",
    					"date": "2021-07-02"
                    }]}));
                    console.log(datas);
    
            var obj1 = {};
            
            datas.datas.forEach(item=>{
                obj1[item.subId] = [];
            });
            console.log(obj1);
            datas.datas.forEach(item=>{
                for(let o in obj1){
                    if(item.subId==o){
                        obj1[o].push(item);
                    }
                }
            });
            console.log(obj1);
            var arrObj = [];
            let i=0;
            for(let o in obj1){
                arrObj[i] = {};
                arrObj[i].name = '文本';
                arrObj[i].display = 'haha';
                arrObj[i].newValue = '文本1';
                arrObj[i].oldValue = '文本';
                arrObj[i].children = obj1[o];
                i++;
            }
    
            console.log(arrObj);
        </script>
    </head>
    <body>
        
    </body>
    </html>

以上代码运行的最终结果如下  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ0NjA0OTI0_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ0NjA0OTI0_size_16_color_FFFFFF_t_70]: /images/20221005/39155612ebe2401bb77debdab11eb031.png