如何通過JavaScript

Question

我想點擊更新按鈕

HTML之前更新上一個單選按鈕的點擊數據的百分比值更新HTML自定義按鈕輸入子屬性：

<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：我的腳本功能不更新按鈕子屬性值。請幫忙。

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

Answer 1

爲了訪問data屬性，你必須做這樣的：

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>