function swapImage(firstImage,secondImage)
{
document.getElementById(firstImage).src=secondImage;
}
function restoreImage(firstImage,secondImage)
{
document.getElementById(firstImage).src=secondImage;
}

function check_form()
{
	err=0;
	
	forma = document.regform;
	
	if (!forma.companyname.value) {
		err=1; forma.companyname.className='textfield_err';
	} else {
		forma.companyname.className='textfield';
	}
	
	if (!forma.name.value) {
		err=1; forma.name.className='textfield_err';
	} else {
		forma.name.className='textfield';
	}
	
	if (!forma.email.value) {
		err=1; forma.email.className='textfield_err';
	} else {
		
		if(!isEmail(forma.email.value))
		{
			err=1; forma.email.className='textfield_err';
		}
		else
		{
			forma.email.className='textfield';
		}
	}
				
	if (err==0)
		return true;
	else
	{
		alert('The data you entered has errors');
		return false;
	}
}

function isEmail(string) 
{
	if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
	{
		return true;
	}
	else
	{
		return false;
	}
}