1、将字符串转化为数组对象

<script>
        var str = "剧情,犯罪,月黑风高"
        var arr = str.split(",");
        console.log(arr);
        var res = []
        arr.forEach(name=>{
            console.log(name);
            res.push({
                name
            })
        })
        console.log(res);
    </script>

2、提取对象中属性的值并生成新的数组对象

<script>
        var obj = {
            top250:["你好666","它的666"],
            comingSoon:["防抖111","节流111"],
            theaters:["放大镜222","防静电222"],
        }
        var arr = []
        var res = []
        /* 1、获取对象中属性的值 */ 
        for(key in obj){
            console.log(obj[key]);
            /* 2、需要将属性的值整合到一个数组中去 */ 
            arr.push(...obj[key]);  
        }
        console.log(arr);
        /* 3、对数组中每一项的值,过滤 */ 
        arr.forEach(name=>{
            var name = name.replace(/\d/g,"");
            res.push({
                name
            })
        })
        console.log(res);
    </script>

3、将html标签字符串转化为JSON对象

<script>
        var str = `<span>9.7<span><span>-248人评价</span><br>
        <span>9.5<span><span>-48人评价</span><br>
        <span>9.6<span><span>-508人评价</span>`
        /* 1、以<br>分割字符串为数组 */ 
        var arr = str.split("<br>");
        // console.log(arr);
        /* 2、将数组中的每一项html标签去除  9.7-248人评价 */ 
        var reg = /<[^<>]+>/g;
        var res = arr.map(item=>{
            // console.log(item.trim().replace(reg,""));
            return item.trim().replace(reg,"");
        })
        console.log(res);
        /* 3、[9.7,248人评价].... */ 
        var lists = [];
        res.forEach(item=>{
            console.log(item.split("-"))
            lists.push(item.split("-"))
        })
        console.log(lists);
        var sum = []
        var rNum = /[^\d]/g;
        lists.forEach(item=>{
            var star = item[0]
            var rating = item[1].replace(rNum,"")
            sum.push({
                star,
                rating
            })
        })
        console.log(sum);
    </script>

4、将字符串转化为JSON对象的应用

<script>
        var str = `
        [{"name":"李四666","data":[2019,10,11]},
        {"name":"张三666","data":[2017,10,11]},
        {"name":"王五点击666","data":[2018,10,11]}]
        `
        var arr = JSON.parse(str);
        console.log(arr);
        var list = []
        arr.forEach(item=>{
            console.log(item)
            var {name,data} = item;
            name = name.replace(/\d/g,"")+"...";
            data = data.join("-")
            list.push({
                name,
                data
            })
        })
        console.log(list)
    </script>

5、复杂对象提取不同值转化为数组

<script>
        var arr = {
            A:[{city:"武汉"},{city:"广州"}],
            B:[{city:"深圳"},{city:"广州"}],
            C:[{city:"上海"},{city:"武汉"}]
        }
        var list = [];
        for(var key in arr){
            console.log(arr[key]);
            list.push(...arr[key]);
        }
        console.log(list);
        var res = []
        list.forEach(item=>{
            item = item.city;
            if(res.indexOf(item)==-1){
                res.push(item)
            }
        })
        console.log(res);
    </script>

Object.values()方法优化

<script>
        var arr = {
            A:[{city:"武汉"},{city:"广州"}],
            B:[{city:"深圳"},{city:"广州"}],
            C:[{city:"上海"},{city:"武汉"}]
        }
        var values = Object.values(arr);
        var res = []
        values.forEach(item=>{
            // console.log(item);
            item.forEach(city=>{
                console.log(city);
                var city = city.city
                if(res.indexOf(city)==-1){
                    res.push(city)
                }
            })
        })
        console.log(res);
    </script>