使用javascript设置表单值

问题描述:

以下是我正在使用的表单的剪辑。我正在使用JavaScript将美元和美分的值设置为2和00,但不起作用。任何人都可以纠正这个?谢谢使用javascript设置表单值

<select class="element select medium" id="element_8" name="element_8" onChange="update_txt()"> 
     <option value="" selected="selected"></option> 
     <option value="First option" >First option</option> 
     <option value="Second option" >Second option</option> 
     <option value="Third option" >Third option</option> 
</select> 
     <input id="subtotal" name="subtotal" class="element text currency" size="10" value="" type="text" /> .  
     <label for="subtotal">Dollars</label> 


     <input id="subtotalcents" name="subtotalcents" class="element text" size="2" maxlength="2" value="" type="text" /> 
     <label for="subtotalcents">Cents</label> 

     <script>function update_txt(){ 
       price = document.getElementById('element_8').value; 
       document.getElementById('element_7').value = price; 
       document.getElementById('element_7').focus(); 
       document.getElementbyId('subtotal').value ='2'; 
       document.getElementbyId('subtotalcents').value ='00'; 
     } 
     </script> 
+1

你在哪里调用函数? – JJJ

+0

在一个下拉菜单onchange。我的JavaScript的第一位工作,但只是最后两行给我麻烦。 – DotyDot

+0

'

这是document.getElementById('subtotal').value ='2';是资金“B”

function update_txt(){ 
       price = document.getElementById('element_8').value; 
       document.getElementById('element_7').value = price; 
       document.getElementById('element_7').focus(); 
       document.getElementById('subtotal').value ='2'; 
       document.getElementById('subtotalcents').value ='00'; 
     } 

PS:有以U提供的代码没有element_7,但希望它是存在于实际代码UR使用。

+0

谢谢你好先生没有意识到 – DotyDot

+0

是元素7是选择或文本框 –

+0

@DotyDot:你的欢迎。 – Pbk1303

<html> 
<head> 
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script> 


<script>function update_txt(){ 
    debugger 
       price = document.getElementById('element_8').value; 
       document.getElementById('element_7').value = price; 
       document.getElementById('element_7').focus(); 
       document.getElementById('subtotal').value ='2'; 
       document.getElementById('subtotalcents').value ='00'; 
     } 
     </script> 

</head> 
<body> 

<select class="element select medium" id="element_8" name="element_8" onChange="update_txt()"> 
     <option value="" selected="selected"></option> 
     <option value="First option" >First option</option> 
     <option value="Second option" >Second option</option> 
     <option value="Third option" >Third option</option> 
</select> 
     <input id="element_7" name="element_7" class="element text currency" size="10" value="" type="text" /> . 
     <input id="subtotal" name="subtotal" class="element text currency" size="10" value="" type="text" /> .  
     <label for="subtotal">Dollars</label> 


     <input id="subtotalcents" name="subtotalcents" class="element text" size="2" maxlength="2" value="" type="text" /> 
     <label for="subtotalcents">Cents</label> 

</body> 
</html>