The click() method simulates a click on the submit button. Note that if you have an onClick event handler assigned to this button, it will not be executed.
<html>
<head>
<script language="JavaScript">
<!--
function submitForm(){
if(document.myForm.myText.value == ""){
alert("Please enter some text first");
}else{
document.myForm.mySubmit.click();
}
}
-->
</script>
</head>
<body>
<form name="myForm">
Please Enter some text and click the link.<br>
<input type=TEXT value="" name="myText">
<input type=SUBMIT value="Submit" name="mySubmit">
</form>
<br>
<a href="javascript:submitForm()">Click here to submit the form</a>
</body>
</html>