Javascript复选框表单验证

时间:2012-06-22 18:18:32

标签: javascript forms validation

我正在尝试将此链接用作我的资源:http://www.w3schools.com/js/js_form_validation.asp

我理解它对文本框的作用,但是如何让它检测复选框的表单验证?例如,如果我有一个带有复选框的页面(都具有相同的“名称”值),我想确保至少有一个框被选中...我该怎么做?如果未选中复选框,我对发送邮件请求有点困惑,以及javascript应如何捕获它。谢谢。

编辑----

有了它的工作,这里是未来人的一些代码:

<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
function Validate(){
   if(!validateForm()){
       alert("Something happened");
       return false;
   }
return true
}
function validateForm()
{
    var c=document.getElementsByTagName('input');
    for (var i = 0; i<c.length; i++){
        if (c[i].type=='checkbox')
        {
            if (c[i].checked){return true}
        }
    }
    return false;
}
</script>
</head>
<body>
<form name="myForm" action="demo_form.asp" onsubmit="return Validate()" method="post">
Value: <input type="checkbox" name="fname" value="value">
Value2: <input type="checkbox" name="fname" value="value2">
...<more boxes here>
<input type="submit" value="Submit">
</form>
</body>
</html>

2 个答案:

答案 0 :(得分:1)

这是一个例子,它可以满足您的要求并可以在此页面中进行测试:

&#13;
&#13;
function Validate(){
   if(!validateForm()){
       alert("You must check atleast one of the checkboxes");
       return false;
   }
return true
}
function validateForm()
{
    var c=document.getElementsByTagName('input');
    for (var i = 0; i<c.length; i++){
        if (c[i].type=='checkbox')
        {
            if (c[i].checked){return true}
        }
    }
    return false;
}
&#13;
<form name="myForm" action="demo_form.asp" onsubmit="return Validate()" method="post">
Option 1: <input type="checkbox" name="option1" value="1"><br />
Option 2: <input type="checkbox" name="option2" value="2"><br />
<input type="submit" value="Submit Form">
</form>
&#13;
&#13;
&#13;

答案 1 :(得分:0)

&#13;
&#13;
function ValidateForm(form){
ErrorText= "";
if ( ( form.gender[0].checked == false ) && ( form.gender[1].checked == false ) )
{
alert ( "Please choose your Gender: Male or Female" );
return false;
}
if (ErrorText= "") { form.submit() }
}
&#13;
<form name="feedback" action="#" method=post>
Your Gender: <input type="checkbox" name="gender" value="Male"> Male
<input type="checkbox" name="gender" value="Female"> Female

<input type="reset" value="Reset">
  <input type="button" name="SubmitButton" value="Submit" onClick="ValidateForm(this.form)">
</form>
&#13;
&#13;
&#13;

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