javascript - QuerySelector 设置文本值

Question

我有这个循环应该设置 <input type="text"/>值为无并更新占位符。当我登录节点时它工作正常但是 value和 placeholder没有更新？怎么了？

数据是一个 JSON 对象。

var data = {"password":"password","username":"xhinii"};

JS :

var data = {"password":"password","username":"xhinii"};

for(var prop in data) {
    console.log(document.querySelector('input[name = "' + prop + '"]')); //works fine. logs the node.
    document.querySelector('input[name = "' + prop + '"]').value = ''; //doesn't work
    document.querySelector('input[name = "' + prop + '"]').setAttribute('placeholder', data[prop]);//doesn't work
}

Answer 1

你不应该解析一个对象只是使用它:

var data= {"password":"password","username":"xhinii"};

for(var prop in data) {
    document.querySelector('input[name = "' + prop + '"]').value = prop; 
    document.querySelector('input[name = "' + prop + '"]').setAttribute('placeholder', data[prop])
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input name='password' />
<input name='username' />