//function to check empty fields
function isEmpty(strFirstName, strLastName)
{
	//change "field1, to your field names
	strFirstName = document.forms[0].FirstName.value
	strLastName = document.forms[0].LastName.value
	//name field
	if (strFirstName == "" || strFirstName == null || !isNaN(strFirstName) || strFirstName.charAt(0) == ' ')
	{
		alert("Please enter your First Name")
		return false;
	}
	if (strLastName == "" || strLastName == null || !isNaN(strLastName) || strLastName.charAt(0) == ' ')
	{
		alert("Please enter your Last Name")
		return false;
	}
	return true;
}

//function to check valid email address
function isValidEmail(strEmail)
{
	validRegExp = /^[^@]+@[^@]+.[a-z]{2,}$/i;
	strEmail = document.forms[0].Email.value;
	// search email text for regular exp matches
	if (strEmail.search(validRegExp) == -1)
	{
		alert('Please enter a valid email address');
		return false;
	}
	return true;
}

//function that performs all functions, defined in the onsubmit event handler
function check(form)
{
	if (isEmpty(form.FirstName)){
		if (isEmpty(form.LastName)){
			if (isValidEmail(form.Email)){
				return true;
			}
		}
	}
	return false;
}

function MM_preloadImages()
{ //v3.0
	var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
	var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
	if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_swapImgRestore()
{ //v3.0
	var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_findObj(n, d)
{ //v4.01
	var p,i,x;	if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
	d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
	if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
	for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
	if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage()
{ //v3.0
	var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
	if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}