function test(){
if(document.getElementById("check1").checked
&& document.getElementById("text1").value=="")
return false;
if(document.getElementById("check2").checked
&& document.getElementById("text2").value=="")
return false;
return true;
}
if(document.getElementById("check1").checked
&& document.getElementById("text1").value=="")
return false;
if(document.getElementById("check2").checked
&& document.getElementById("text2").value=="")
return false;
return true;
}
<body>
<input type=checkbox id=check1> <input id=text1><br>
<input type=checkbox id=check2> <input id=text2><br>
<input type=button onclick="alert(test())">
</body>
<script language="javascript">
function test(){
if(document.getElementById("check1").checked
&& document.getElementById("text1").value=="")
return false;
if(document.getElementById("check2").checked
&& document.getElementById("text2").value=="")
return false;
return true;
}
</script>
</html>
可能和楼主期望的效果有差距^_^
<body>
<div align="center">
<table border="0" width="780">
<tr>
<td align="right">新闻类型:</td>
<td width="655">
<input type=checkbox id=check1 name="C1" value="ON">头条新闻</td>
</tr>
<tr>
<td valign="top" align="right">简介:</td>
<td width="655">
<form method="POST" action="#">
<p><textarea rows="5" name="S1" cols="20"></textarea></p>
<p><input type="submit" value="提交" name="B1">
<input type="reset" value="重置" name="B2"></p>
</form>
</td>
</tr>
</table>
</div>
</body>
</html>就是当勾选复选框C1后,文本框S1必须填写,否则提示"文本框内容须填写".我要的就是这个验证代码.
<script>
function check(){
if(document.getElementById("check1").checked && document.all.S1.value=="")
return false;
return true;
}
</script>
建议早该把代码贴出来了,这样也不会绕弯
{
if(form.S1.value==""&& document.getElementById("check1").checked==true)
{
alert("不能为空");
return false;
}
}<form onsubmit="return check(this)"
<body>
<script language="javascript">
function check(form1)
{
if(form.S1.value==""&& document.getElementById("c1").checked==true)
{
alert("不能为空");
return false;
}
}<form onsubmit="return check(this)"
</script>
<div align="center">
<table border="0" width="780">
<tr>
<td align="right">新闻类型:</td>
<td width="655">
<input type=checkbox id=check1 name="C1" value="ON">头条新闻</td>
</tr>
<tr>
<td valign="top" align="right">简介:</td>
<td width="655">
<form method="POST" action="#" name="form1">
<p><textarea rows="5" name="S1" cols="20"></textarea></p>
<p><input type="submit" value="提交" name="B1">
<input type="reset" value="重置" name="B2"></p>
</form>
</td>
</tr>
</table>
</div>
</body>
</html>
<body>
<script language="javascript">
function check(){
if(document.getElementById("check1").checked && document.all.S1.value=="")
return false;
return true;
}
</script>
<div align="center">
<table border="0" width="780">
<tr>
<td align="right">新闻类型:</td>
<td width="655">
<input type=checkbox id=check1 name="C1" value="ON">头条新闻</td>
</tr>
<tr>
<td valign="top" align="right">简介:</td>
<td width="655">
<form method="POST" action="#" name="form1" onsubmit="return check()">
<p><textarea rows="5" name="S1" cols="20"></textarea></p>
<p><input type="submit" value="提交" name="B1">
<input type="reset" value="重置" name="B2"></p>
</form>
</td>
</tr>
</table>
</div>
</body>
</html>两个都不行,帮我看看哪里错
<body>
<script language="javascript">
function checkForm(form)
{
if(form.C1.checked && form.S1.value == "")
{
alert('文本框内容须填写');
return false;
}
}
</script>
<div align="center">
<form method="POST" action="#" onsubmit="return checkForm(this);">
<table border="0" width="780">
<tr>
<td align="right">新闻类型:</td>
<td width="655">
<input type=checkbox id=check1 name="C1" value="ON">头条新闻</td>
</tr>
<tr>
<td valign="top" align="right">简介:</td>
<td width="655">
<p><textarea rows="5" name="S1" cols="20"></textarea></p>
<p><input type="submit" value="提交" name="B1">
<input type="reset" value="重置" name="B2"></p>
</td>
</tr>
</table>
</div></form>
</body>
</html>