代码如下:
<a href='javascript:void(0);' class="useCard" id="useCard">使用礼品卡</a>
<div class="card" id="cardInfo" style="display:none">
<form >
<input type="hidden" name="card_use" id="card_use" value='false'>
卡号:<input type="text" name="card_code" id="card_code" value=""><br/><br/>
密码:<input type="text" name="card_passwd" id="card_passwd" value=""><br/><br/>
<input type="button" id="confirmUseCard" value="确认使用">
</form>
</div>
window.onload=function()
{
var userCardButton = document.getElementById('useCard');
var cardBox = document.getElementById('cardInfo');
var confirmUseCardButton = document.getElementById('confirmUseCard');
userCardButton.onclick=function()
{
if(cardBox.style.display=='none')
{
cardBox.style.display='block';
}
else
{
cardBox.style.display='none';
}
}
confirmUseCardButton.onclick=function()
{
var card_code = document.getElementById('card_code').value;
var card_pass = document.getElementById('card_pass').value;
if(card_code.length<=0 || card_code=='')
{
layer.alert('请填写卡号');
return
}
else if(card_pass.length<=0 || card_pass=='')
{
layer.alert('请填写卡密码');
return
}
else
{
}
}
}
执行后报错信息Uncaught TypeError: Cannot read property 'value' of null
,请问我错在什么地方?
var card_pass = document.getElementById('card_passwd').value;
/* var card_code = document.getElementById('card_code').value;
var card_pass = document.getElementById('card_pass').value;*///报错
var card_code = $('#card_code').val();
var card_pass = $('#card_pass').val();//运行正确
煞笔的原生JS