Insert data problem after javascript validation

[Sul]

Hey,

I have a form which is validated client-side by some simple Javascript:

function validatecommentsform()
{
	if(document.addcommentform.txtName.value == '')
	{
		alert('Please fill in the Name field.');
		return false;
	}
	else if(document.addcommentform.txtComment.value == '')
	{
		alert('Comment field cannot be empty.');
		return false;
	}
	else
	{
		document.addcommentform.commentformsubmitbutton.disabled = true
		return true;
	}
}

Then on the form my action points to the same page which has the code something like:

If($_POST['Submit'])
{
  //code to insert data into db here
}

The problem is that if I use javascript to validate the form, no data seems to be inserted into the database. If I remove the onsubmit event from the form it then works.

[devinemke]

because your javascript disables the submit button, thus, there is no $_POST['Submit']

[Sul]

Ah.. thanks! It worked. However now I haven't got a way of preventing people from accidentally submitting twice.. Is there another way of doing this?

[devinemke]

you could keep the javascript the way it is and change the PHP to look for some other way of knowing that the form was submitted, like using a hidden form field.