Javascript validation check

There ate two javascript validation function i have made.

First one check empty field using id. We may use field id by an array as bellow. This function check empty field and if found empty field then focus that field also. We may use here another condition like email, phone number check. I think this will be reduce line number of code and time also.
Example:
<form method=”post” action=”<?=$_SERVER[‘PHP_SELF’]?>” onSubmit=”return checkClientForm();”>
<input type=”text” name=”name” id=”name” value=”” tabindex=”1″ /><br />
<input type=”text” name=”title” id=”title” value=”” tabindex=”2″ /><br />
<input type=”text” name=”description” id=”description” value=”” tabindex=”3″ /><br />
<input type=”submit” name=”submit” value=”Save” tabindex=”4″ />
</form>

Second one check file type like image. We may use this function by onchange element. If the file type dose not match then this will give a alert and clear the field also.

Example:
<input type=”file” name=”image” id=”image” value=”” onchange=”checkPhoto()” />

<script language=”javascript” type=”text/javascript”>
function checkClientForm(){
var cont;
var allid = new Array(“name”,”title”,”description”); //you may add more
var msg;
for (var i=0; i<=allid.length-1; i++){
cont=document.getElementById(allid[i]).value;
if(cont.length==0){
alert(“You should fill the required fields properly”);
document.getElementById(allid[i]).focus();
return false;
}
}
return true;
}

function checkPhoto(){
if( (document.getElementById(‘image’).value.split(‘.’)[1]!=’jpg’) && (document.getElementById(‘image’).value.split(‘.’)[1]!=’jpeg’) && (document.getElementById(‘image’).value.split(‘.’)[1]!=’JPG’) && (document.getElementById(‘image’).value.split(‘.’)[1]!=’JPEG’) && (document.getElementById(‘image’).value.split(‘.’)[1]!=’png’) && (document.getElementById(‘image’).value.split(‘.’)[1]!=’PNG’)){ alert(“Sorry, This type of file is not allowed to upload.”); document.getElementById(‘image’).value=”; document.getElementById(‘image’).focus(); return false; }
}
</script>