javascript - Show me if all inputs are empty -

i need build such 4 inputs must specified such if there nothing in name must appear trouble nothing written in name.

i want want out of not have use such can create user or send email must have written in every input form.

i have done this:

<form action="#" method="post" name="kontakt_box">                 <span id="myhint" class="info_box_kontakt"></span>                 <br />                 <label>navn<br /><input type="text" name="navn" class="new" placeholder="navn"></label><br />                 <label>efternavn<br /><input type="tel" name="efternavn" class="new" placeholder="efternavn"></label><br />                 <label>email<br /><input type="email" name="email" class="new" placeholder="email"></label><br />                 <label>tekst<br /><textarea name="tekst" cols="35" rows="10" class="new"></textarea></label><br />                 <label><input type="submit" name="send" value="send" class="new"></label>             </form> 

javascript here:

document.kontakt_box.navn.onfocus=function() {     document.getelementbyid('myhint').innerhtml = "angive et navn!"; } document.kontakt_box.navn.onblur=function() {     document.getelementbyid('myhint').innerhtml = ""; } //efternavn document.kontakt_box.efternavn.onfocus=function() {     document.getelementbyid('myhint').innerhtml = "angive et efternavn!"; } document.kontakt_box.efternavn.onblur=function() {     document.getelementbyid('myhint').innerhtml = ""; } //email document.kontakt_box.email.onfocus=function() {     document.getelementbyid('myhint').innerhtml = "angive en email!"; } document.kontakt_box.email.onblur=function() {     document.getelementbyid('myhint').innerhtml = ""; }  document.kontakt_box.send = function(){     alert('husk noget tekst!');     return false; } 

it's first javasciprt task page, better me there may errors or think it's strange made​​.

your last function may this:

document.kontakt_box.onsubmit = function(){     var navn = document.kontakt_box.navn.value,         efternavn = document.kontakt_box.efternavn.value,         email = document.kontakt_box.email.value,         tekst = document.kontakt_box.tekst.value;     if(!navn || !efternavn || !email || !tekst) {         alert('husk noget tekst!');         return false;     } }; 

and add ; afret each callback function assignment.

working example here http://jsbin.com/enovex/1/edit