这有什么不对？复选框不起作用

Question

我正在尝试使隐藏/显示段落的复选框,但出于某种原因,当我单击复选框时,段落不会出现,这里是JavaScript代码:

function showPara()
{
    document.getElementById("first").style.visibility=(document.formex.firstpara.checked) ? "block" : "hidden";
    document.getElementById("second").style.visibility=(document.formex.secondpara.checked) ? "block" : "hidden";
    document.getElementById("third").style.visibility=(document.formex.thirdpara.checked) ? "block" : "hidden";
    return true:
}

这是HTML代码:

<p id="first">This is a paragraph</p>
<p id="second">This is a paragraph</p>
<p id="third">This is a paragraph</p>

<form name="formex">
    <input type="checkbox" name="firstpara" onClick="showPara();"/>First Paragraph<br />
    <input type="checkbox" name="secondpara" onClick="showPara();"/>Second Paragraph<br />
    <input type="checkbox" name="thirdpara" onClick="showPara();"/>Third Paragrpah<br />
</form>

Answer 1

没有visibility: block,所以hidden没有被改变.使用visibility: visible.您还在函数中有语法错误(return true;vs. return true:).

http://jsfiddle.net/frKXN/1/