function isEmailAddr(email)
{
  var result = false;
  var theStr = new String(email);
  var index = theStr.indexOf("@");
  if (index > 0)
  {
    var pindex = theStr.indexOf(".",index);
    if ((pindex > index+1) && (theStr.length > pindex+1))
	result = true;
  }
  return result;
}

function validRequired(formField,fieldLabel)
{
	var result = true;
	
	if (formField.value == "")
	{
		alert('Please enter a value for the "' + fieldLabel +'" field.');
		/*formField.focus();*/
		result = false;
	}
	
	return result;
}

function validPasswd(formField1,formField2)
{
	var result = true;
	
	if (formField1.value != formField2.value)
	{
		alert('Password fields do not match. Please try again!');
		formField1.focus();
		result = false;
	}
	
	return result;
}

function isMatch(formField1,formField2, fieldLabel)
{
	var result = true;
	
	if (formField1.value == formField2.value)
	{
		alert('"' + fieldLabel +'" fields are the same. Please try again!');
		formField1.focus();
		result = false;
	}
	
	return result;
}


function allDigits(str)
{
	return inValidCharSet(str,"0123456789.");
}

function isValidLength(str,count)
{
	var result = true;

	if(str.length != 0 && str.length != count)
		result = false;

	return result;
}


function inValidCharSet(str,charset)
{
	var result = true;

	// Note: doesn't use regular expressions to avoid early Mac browser bugs	
	for (var i=0;i<str.length;i++)
		if (charset.indexOf(str.substr(i,1))<0)
		{
			result = false;
			break;
		}
	
	return result;
}

function validEmail(formField,fieldLabel,required)
{
	var result = true;
	
	if (required && !validRequired(formField,fieldLabel))
		result = false;

	if (result && ((formField.value.length < 3) || !isEmailAddr(formField.value)) && formField.value.length > 0)
	{
		alert("Please enter a complete email address in the form: yourname@yourdomain.com");
		/*formField.focus();*/
		result = false;
	}
   
  return result;

}

function validNum(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		if (!allDigits(formField.value))
 		{
 			alert('Please enter a number for the "' + fieldLabel +'" field.');
			/*formField.focus();*/
			result = false;
		}
	} 
	
	return result;
}

function validNumLength(formField,fieldLabel,length,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 		{
 		if (!allDigits(formField.value) || !isValidLength(formField.value,length))
 			{
 			alert('Please enter a "' + length +'" digit value for the "' + fieldLabel +'" field.');
			/*formField.focus();*/
			result = false;
			}
		} 
	
	return result;
}



function validInt(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		var num = parseInt(formField.value,10);
 		if (isNaN(num))
 		{
 			alert('Please enter a number for the "' + fieldLabel +'" field.');
			/*formField.focus();*/
			result = false;
		}
	} 
	
	return result;
}


function validDate(formField,fieldLabel,required)
{
	var result = true;

	if (required && !validRequired(formField,fieldLabel))
		result = false;
  
 	if (result)
 	{
 		var elems = formField.value.split("/");
 		
 		result = (elems.length == 3); // should be three components
 		
 		if (result)
 		{
 			var month = parseInt(elems[0],10);
  			var day = parseInt(elems[1],10);
 			var year = parseInt(elems[2],10);
			result = allDigits(elems[0]) && (month > 0) && (month < 13) &&
					 allDigits(elems[1]) && (day > 0) && (day < 32) &&
					 allDigits(elems[2]) && ((elems[2].length == 2) || (elems[2].length == 4));
 		}
 		
  		if (!result)
 		{
 			alert('Please enter a date in the format MM/DD/YYYY for the "' + fieldLabel +'" field.');
			/*formField.focus();*/
		}
	} 
	
	return result;
}

function validButton(formButtonSet, buttonSetLabel)
{
	var result = true;
	
    var count = -1;
    for (var i=formButtonSet.length-1; i > -1; i--)
		{
        if (formButtonSet[i].checked)
			{
			count = i; i = -1;
			}
    	}
		
    if (count > -1)
		{
		//return btn[cnt].value;
		result = true;
		}
    else
		{
		result = false;
		}
		
  	if (!result)
 		{
 			alert('Please make a selection for the "' + buttonSetLabel +' " radio button group.');
		}
		
	return result;
}
  

/*
Sample Form Tag
<form action="form.php" method="post" onSubmit="return validate_form(this)">
</form>

Sample Validate function

function validate_form(theForm)
{
	if (!validRequired(theForm.username,"Screen Name"))
		return false;
	if (!validRequired(theForm.gid,"Group"))
		return false;
	if (!validRequired(theForm.first_name,"First Name"))
		return false;
	if (!validRequired(theForm.last_name,"Last Name"))
		return false;
	if (!validEmail(theForm.email,"Email",true))
		return false;
	if (!validRequired(theForm.phone_h,"Phone"))
		return false;
	if (!validPasswd(theForm.passwd,theForm.passwd2))
		return false;
	if (!validEmail(theForm.email,"Email",true))
		return false;
	if (!validRequired(theForm.card_name,"Name on Card"))
		return false;
	if (!validNum(theForm.card_num,"Card Number",true))
		return false;
	if (!validRequired(theForm.month,"Expiry Month"))
		return false;
	if (!validDate(theForm.available,"Date Available",true))
		return false;
	if (!validButton(theForm.contract_type,"Contract Type"))
		return false;

		// <--------- End
	
	return true;
}

*/