如何通过JavaScript

Question

我想点击更新按钮

HTML之前更新上一个单选按钮的点击数据的百分比值更新HTML自定义按钮输入子属性：

<input type="radio" name="percentage" value="50" onclick="changeVal(this.value)"> Happy 50 percent</input> 

</br> 

<input type="radio" name="percentage" value="75" onclick="changeVal(this.value)"> Happy 75 percent</input> 
</br> 

<button class="btn btn-danger my-btn" id = "myUpdateBtn" data-id="1" data-name="John" data-summary="John is Happy" data-percent="50" >Click to Update</button> 

的javascript：我的脚本功能不更新按钮子属性值。请帮忙。

changeVal(val){ 
alert(val); 
document.getElementById("myUpdateBtn").value('data-price') = val; 
} 

Answer 1

为了访问data属性，你必须做这样的：

var val = document.getElementById('21').dataset.id; 
 
var msg = document.getElementById('21').dataset.name; 
 

 
alert(val); //Alert '21' 
 
alert(msg); //Alert 'HiDiv' 
 

 
document.getElementById('21').dataset.lastName = 'Rod'; //Create new data attribute 
 

 
console.log(document.getElementById('21')); //View changes

<div data-id='21' id='21' data-name = 'HiDiv'> 
 

 
</div>