onSubmit returning false is not working

问题

I'm completely confused ... I'd swear this was working yesterday ... I woke up this morning and all my forms stopped to work in my project.

All the forms have a "onsubmit" to a function that returns false since it's an ajax call, so the form is never sent.

After a lot of tests, I simplified the question to this piece of code:

<html>
<head>
<script type="text/javascript">
 function sub()
 {
  alert ("MIC!");
  return false;
 }
</script> 
</head>
<body>

<form method = "post" id = "form1" onsubmit = "return sub()">
 input: <input type="text" name="input1" >
    <a href="#" onClick="document.getElementById('form1').submit();">button</a> 
</form>

</body>
</html>

I would swear that this works perfectly, but today is nor working :D

Why if I press the button the form is sent ?

I know it's a total newbie question, but I'm stuck

Thank you !

回答1:

Browsers do not call the onSubmit event on the form if you call submit() programmatically.

回答2:

It seems that the 'submit()' function bypasses the 'form' tags 'onsubmit' event in Firefox and IE8. If you use a submit button, then it works as expected:

<html>
<head>
<script type="text/javascript">
 function sub()
 {
  alert ("MIC!");
  return false;
 }
</script> 
</head>
<body>

<form method = "post" action="http://google.com" id = "form1" onsubmit = "return sub();">
 input: <input type="text" name="input1" >
     <input type="submit">
</form>

</body>
</html>

回答3:

The onsubmit event only fires for normal form submissions. It does not fire when the JavaScript submit() method is called.

The best solution is to use a normal submit button here.

If you want to continue with using a link to the top of the page (which isn't unobtrusive, progressive, or graceful) then you need to call the sub() function explicitly and test its return value before deciding if you should call submit() or not.

回答4:

You could use jquery preventDefault method.

$(function () {
        $('#repForm').bind('submit', function (e) {
            var isValid = true;
            if (btnname == 'test') {
                isValid = ValidateEmailID();
            }
            else {
                isValid = ValidateSomething();
            }

            if (!isValid) {
                e.preventDefault();
            }
        });
    });

回答5:

Try to change you "button" code like that

<a href="#" onClick="return document.getElementById('form1').onsubmit();">button</a>

回答6:

I suspect he wanted to use a form button that was not of the submit type. In this case, you can also use:

 <input type="button" value="Submit" onclick="if( sub()) document.getElementById('form1').submit()">

Another tip I give is to use the name attribute in all forms, as it is much easier to use: document.form1.submit() instead of document.getElementById('form1').submit(). It is crossbrowser and work in all of them. getElementById is great but not necessary for forms.

回答7:

I've got the same issue (I was using IE 8),

following code is NOT working:

<form method="post" id="form1" onsubmit="sub">
<form method="post" id="form1" onsubmit="sub()">
<form method="post" id="form1" onsubmit="return sub()">

and following code is WORKING,

<form method="post" id="form1" onsubmit="return(sub())">

I just follow the sample here

And please note that:

The submit method does not invoke the onsubmit event handler.

Submit a form using the INPUT TYPE=submit, INPUT TYPE=image, or BUTTON TYPE=submit object.

回答8:

Add "return" in all your onsubmit statements in your form tag...e.g. onsubmit="return validate_function()" this way the return false or return true in your validate function is posted as the result to the return command in your onsubmit.

回答9:

<head>
  <script type="text/javascript">
   function sub(e)
   {
     e.preventDefault();
     alert ("MIC!");
     return false;
   }
  </script> 
 </head>
 <body>
   <form method = "post" id = "form1" onsubmit = "return sub(event);">
   </form>

回答10:

Check basic syntaxes and structures... then Check your other forms on your page or input boxes with no form... I had the same problem (or similar: pressing enter in the input box would cause the form to send) ...

I copy pasted the samples above and loaded the page. They worked and mine did not, so i tweaked the formatting and even rewrote it.

来源：https://stackoverflow.com/questions/2543963/onsubmit-returning-false-is-not-working

标签

return

onsubmit