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技术 2022年11月21日
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循环可以将代码块执行指定的次数.如果您希望一遍又一遍地运行相同的代码,并且每次的值都不同,那么使用循环是很方便的。迭代语句又叫循环语句。

JavaScript 支持不同类型的循环:

  • for – 循环代码块一定的次数
  • for/in – 循环遍历对象的属性
  • while – 当指定的条件为 true 时循环指定的代码块
  • do/while – 同样当指定的条件为 true 时循环指定的代码块
     var obj = { height: 175, weight: 60 }; //初始化一个对象
console.log(obj);
var keys = Object.keys(obj); //获取对象 obj 属性名组成的数组
console.log(keys);
var values = []; //values用来保存对象 obj 属性值
for(var i = 0, len = keys.length; i < len; i++){
var key = keys[i]; //获取当前索引的键值
values[i] = obj[key]; //在values数组中保存属性值
console.log(values[i]);
}

效果截图:

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