ES6 - 解构(数组和对象)

解构对象

/**
 * 解构：快捷，方便
 * 
 * 对象解构
 */

{
  var expense = {
    type: "es6",
    amount: "45"
  };

  //1.ES5
  // var type = expense.type;
  // var amount = expense.amount;
  // console.log(type, amount); //output: es6 45

  //2.ES6
  const { type, amount, abc } = expense;
  console.log(type, amount, abc);    //output: es6 45 undefined
}

{

  var saveFiled = {
    extension: "jpg",
    name: "girl",
    size: 14040
  };

  //ES5
  function fileSammary1(file) {
    return `${file.name}.${file.extension}的总大小是${file.size};`
  }

  //ES6
  //名字不能变，位置可以乱
  function fileSammary2({ name, size, extension }) {
    return `${name}.${extension}的总大小是${size};`
  }

  console.log(fileSammary1(saveFiled)); //output: girl.jpg的总大小是14040;
  console.log(fileSammary2(saveFiled)); //output: girl.jpg的总大小是14040;
}

其他参考：https://www.cnblogs.com/tangge/p/10473727.html#t3