function CreditsCheckFields()
{
	// we start with a valid form, if something seems to be wrong, it will be set to fase.
	var valid = true;
	
	// get the Button from the document
	var btnSubmit = document.getElementById('btnSubmit');
	
	// get the radio buttons
	var rdbCredit1 = document.getElementById('rdbCredit1'); 
	var rdbCredit2 = document.getElementById('rdbCredit2');
	var rdbCredit3 = document.getElementById('rdbCredit3');


	// get the Bank field
	var ddmBank = document.getElementById('ddmBank');
	
	// check if one of the radio buttons is checked
	if(!rdbCredit1.checked && !rdbCredit2.checked && !rdbCredit3.checked) {
		valid = false;
		CreditsBlnImage('rdbCredits',false);
	}  else {
		CreditsBlnImage('rdbCredits',true);
	}
	
	
	if(ddmBank.value == 0) {
		valid = false;
		CreditsBlnImage(ddmBank.id,false);
	} else {
		CreditsBlnImage(ddmBank.id,true);
	}
	
	if(valid) {
    	btnSubmit.disabled=false;
    } else {
    	btnSubmit.disabled=true;
    }
    
    return valid;
}

function CreditsBlnImage(fieldName, isValid) {
	var imgName = 'img' + fieldName.substr(0, 1).toUpperCase() + fieldName.substr(1);
	var imgValid = document.getElementById(imgName);
	
	if(isValid) {
		imgValid.src = 'images/true.gif';
	} else {
		imgValid.src = 'images/false.gif';
	}
}

function CreditsResetForm() {
	document.getElementById('frmOrder').reset();
	CreditsCheckFields();
}