function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value=="")
  {alert(alerttxt);return false}
else {return true}
}
}

function validate_form(thisform)
{
with (thisform)
{
if ( (username.value==null||username.value=="") && (pass.value==null||pass.value=="") )
	{ alert("You must supply a Username and Pasword");
	username.focus();return false}
if (validate_required(username,"Username must be filled out!")==false)
  {username.focus();return false}
if (validate_required(pass,"Password must be filled out!")==false)
  {username.focus();return false}
}

}
function logout()
{
	window.location="logout.php";
}

function changeImage(img_name, img_src)
{
	document[img_name].src=img_src;
}
function validateUploadForm()
{
	var isFile = document.getElementById('uploadedfile').value;
	if(isFile == null || isFile == "")
	{
		alert('You must select a file to upload'+isFile);
		return false;
	}	
}