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  • 使用reduce 和 entries 实现数据类型的转化

    将二维数组转化为对象

    <!DOCTYPE html>
    <html lang="en">
    <head>
          <meta charset="UTF-8">
          <meta name="viewport" content="width=device-width, initial-scale=1.0">
          <meta http-equiv="X-UA-Compatible" content="ie=edge">
          <title>Document</title>
    </head>
    <body>
          <script>
    let obj = {
          a:1,
          b:2,
          c:3,
          d:4
    }
    // [{text:a ,value:1},{text:b ,value:2},{text:c ,value:3},{text:d ,value:4}]
    console.log(Object.entries(obj)) //[[a:1],[b:2]].....
    let result = Object.entries(obj).map(item =>{
          return {text:item[0],value:item[1]}
    })
    console.log(result)// [{text:a ,value:1},{text:b ,value:2},{text:c ,value:3},{text:d ,value:4}]
          </script>
    </body>
    </html>
    <!DOCTYPE html>
    <html lang="en">
    <head>
          <meta charset="UTF-8">
          <meta name="viewport" content="width=device-width, initial-scale=1.0">
          <meta http-equiv="X-UA-Compatible" content="ie=edge">
          <title>Document</title>
    </head>
    <body>
          <script>
    let obj = [{text:'a' ,value:1},{text:'b' ,value:2},{text:'c' ,value:3},{text:'d' ,value:4}]
    // let obj = {
    //       a:1,
    //       b:2,
    //       c:3,
    //       d:4
    // }
    let result = obj.reduce((pre,cur,index)=>{
          pre[cur.text] = cur.value
          return pre
    },{})
    console.log(result) //{a: 1, b: 2, c: 3, d: 4}
          </script>
    </body>
    </html>

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  • 原文地址:https://www.cnblogs.com/javascript9527/p/13187504.html
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