function isEmail(inputString) {
	regexp=/^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,9})$/;
	if (regexp.test (inputString)) return true 
	else return false;
}

function isEmpty (inputString) {
	if (inputString=='') return true
	else return false;
}

function validateLogin() {
	flag=0;
	
	if (isEmpty(document.getElementById('user').value) || isEmpty(document.getElementById('password').value)) { 
		alert("Fill in your username and password!");
		flag=1;
	}
	
	if (flag==1) {
		return false;
		} else {
		return true;
	}
}

function rusure(m,url) { // message to display
        if(confirm(m)) {
	    document.location = url;
	}
}

// nested tree menu script 

function toggle(id){
    ul = "ul_" + id;
    img = "img_" + id;
    ulElement = document.getElementById(ul);
    imgElement = document.getElementById(img);
    if (ulElement){
            if (ulElement.className == 'closed'){
                    ulElement.className = "open";
                    imgElement.src = "images/opened.gif";
                    }else{
                    ulElement.className = "closed";
                    imgElement.src = "images/closed.gif";
                    }
            }
}