Question

html如何实现勾选复选框实现出现和隐藏

如何实现勾选上面的复选框出现下面的邀请码项，取消勾线则隐藏？？
<div class="register_p">
<input name="" type="checkbox" value=""> 通过邀请码注册
</div>
<div class="field">
<label>邀请码</label>
<input class="width4" type="text" value="" onfocus="clearText(this)" onblur="clearText(this)">

</div>

Answer 1

<div class="register_p">
    <input name="" type="checkbox" value="" onclick="ck(this)" />&nbsp; 通过邀请码注册</div>
<div class="field">
    <label>邀请码</label>
    <input class="width4" type="text" value="" onfocus="clearText(this)" onblur="clearText(this)" />
</div>
</div>
<script>
    var ck = function(dom) {
      	var div = dom.nextElementSibling;
        if (dom.checked) {
        	div.style.display = "block";
        }else{
        	div.style.display = "none";
        }
    }
</script>