it just doesn't work. help! Jquery gets data from a Form

it just doesn't work. help! Jquery gets data from a Form

Html:

<form id="kommentar_form" action="">
<fieldset>
<label for="name" id="label_name" >Name:</label>
<input name="name" id="name" type="text" class="input_text">
<label class="error" for="name" id="name_error">Name is required!</label>
<label for="email" id="label_email">Email:</label>
<input name="email" id="email" type="email" class="input_text">
<label for="email" class="error" id="email_error">Email is required!</label>
<label for="hinterlassen" id="label_kommentar">Kommentar:</label>
<textarea id="hinterlassen" name="message" row="10" cols=20" placeholder="Please enter your Message">
</textarea>
<label for="hinterlassen" id="kommentar_error" class="error">Message is required!</label>
<br>
<button id="form_submit" name="form_submit" type="button">Click!</button>
</fieldset>
</form>


Javascript:

$("button #form_submit").click(function(){
var fname = $("input #name").val();
if(fname == ""){
$("label #name_error").show();
$("input #name").focus();
return false;
}
var femail = $("input #email").val();
if(femail == ""){
$("label #email_error").show();
$("input #email").focus();
return false;
}
var fkommentar = $("textarea #hinterlassen").val();
if(fkommentar == ""){
$("label #kommentar_error").show();
$("textarea #hinterlassen").focus();
return false;
}
});


 Then i want to write a ajax function for inserting data into database.   but it has not already worked.  Pleas help

sorry for my bad English