function checkflds()
{	
	if(document.form.first_name.value.length==0)
	{	window.alert("Please enter your first name.");
		document.form.first_name.focus();
		return false;
	}
	
	if(document.form.last_name.value.length==0)
	{	window.alert("Please enter your last name.");
		document.form.last_name.focus();
		return false;
	}

	len = document.form.email.value.length
	var i=1
	var count=0

	if(document.form.email.value.length == 0)
	{	window.alert("Please supply an Email address.");
		document.form.email.select();
		document.form.email.focus();
		return false;
	}
	while (i<= len){
		if((document.form.email.value.substring(i-1,i) == "@")){
			count = count + 1
		}
		if((document.form.email.value.substring(i-1,i) == " ")){
			count = 2
		}
		i = i + 1;
	}
	if(count != 1)
	{	window.alert("Please enter a valid email address!")
		document.form.email.select();
		document.form.email.focus();
		return false;
	}
}


function OnSubmitCheck() {
var one = checkflds(); // change functionOne() to onsubmit function name
var two = validateCard(document.form.cc_number.value,document.form.cc_type.value,document.form.cc_month.value,document.form.cc_year.value); // change functionTwo() to onsubmit function name
if((one == false) || (two == false)) 
{ 
	return false; 
}
return true;
}

function mod10( cc_number ) { // LUHN Formula for validation of credit card numbers.
	var ar = new Array( cc_number.length );
	var i = 0,sum = 0;


    	for( i = 0; i < cc_number.length; ++i ) {
    		ar[i] = parseInt(cc_number.charAt(i));
    	}
    	for( i = ar.length -2; i >= 0; i-=2 ) { // you have to start from the right, and work back.
    		ar[i] *= 2;							 // every second digit starting with the right most (check digit)
    		if( ar[i] > 9 ) ar[i]-=9;			 // will be doubled, and summed with the skipped digits.
    	}										 // if the double digit is > 9, ADD those individual digits together 


        	for( i = 0; i < ar.length; ++i ) {
        		sum += ar[i];						 // if the sum is divisible by 10 mod10 succeeds
        	}
        	return (((sum%10)==0)?true:false);	 	
    }


        function expired( month, year ) {
        	var now = new Date();							// this function is designed to be Y2K compliant.
        	var expiresIn = new Date(year,month,0,0,0);		// create an expired on date object with valid thru expiration date
        	expiresIn.setMonth(expiresIn.getMonth()+1);		// adjust the month, to first day, hour, minute & second of expired month
        	if( now.getTime() < expiresIn.getTime() ) return false;
        	return true;									// then we get the miliseconds, and do a long integer comparison
    }


        function validateCard(cc_number,cc_type,cc_month,cc_year) {
        	if( cc_number.length == 0 ) {						//most of these checks are self explanitory
        		alert("Please enter a valid card number.");
        		return false;				
        	}
        	for( var i = 0; i < cc_number.length; ++i ) {		// make sure the number is all digits.. (by design)
        		var c = cc_number.charAt(i);


            		if( c < '0' || c > '9' ) {
            			alert("Please enter a valid card number. Use only digits. do not use spaces or hyphens.");
            			return false;
            		}
            	}
            	var length = cc_number.length;			//perform card specific length and prefix tests


                	switch( cc_type ) {
                		case 'a':


                    			if( length != 15 ) {
                    				alert("Please enter a valid American Express Card number.");
                    				return false;
                    			}
                    			var prefix = parseInt( cc_number.substring(0,2));


                        			if( prefix != 34 && prefix != 37 ) {
                        				alert("Please enter a valid American Express Card number.");
                        				return false;
                        			}
                        			break;
                        		case 'd':


                            			if( length != 16 ) {
                            				alert("Please enter a valid Discover Card number.");
                            				return false;
                            			}
                            			var prefix = parseInt( cc_number.substring(0,4));


                                			if( prefix != 6011 ) {
                                				alert("Please enter a valid Discover Card number.");
                                				return false;
                                			}
                                			break;
                                		case 'm':


                                    			if( length != 16 ) {
                                    				alert("Please enter a valid MasterCard number.");
                                    				return false;
                                    			}
                                    			var prefix = parseInt( cc_number.substring(0,2));


                                        			if( prefix < 51 || prefix > 55) {
                                        				alert("Please enter a valid MasterCard Card number.");
                                        				return false;
                                        			}
                                        			break;
                                        		case 'v':


                                            			if( length != 16 && length != 13 ) {
                                            				alert("Please enter a valid Visa Card number.");
                                            				return false;
                                            			}
                                            			var prefix = parseInt( cc_number.substring(0,1));


                                                			if( prefix != 4 ) {
                                                				alert("Please enter a valid Visa Card number.");
                                                				return false;
                                                			}
                                                			break;
                                                	}
                                                	if( !mod10( cc_number ) ) { 		// run the check digit algorithm
                                                		alert("Sorry! this is not a valid credit card number.");
                                                		return false;
                                                	}
                                                	if( expired( cc_month, cc_year ) ) {							// check if entered date is already expired.
                                                		alert("Sorry! The expiration date you have entered would make this card invalid.");
                                                		return false;
                                                	}
                                                	
                                                //	return true; // at this point card has not been proven to be invalid
                                            }
                                            //-->