
//-------------------------------------------------------------------
// isDigit(value)
//   Returns true if value is a 1-character digit
//-------------------------------------------------------------------
function isDigit(num) {
	if (num.length>1){return false;}
	var string="1234567890";
	if (string.indexOf(num)!=-1){return true;}
	return false;
	}
	
//-------------------------------------------------------------------
// isInteger(value)
//   Returns true if value contains all digits
//-------------------------------------------------------------------
function checkDigits(val){
	if (isBlank(val)){return false;}
	for(var i=0;i<val.length;i++){
		if(!isDigit(val.charAt(i))){return false;}
		}
	return true;
	}
	
//-------------------------------------------------------------------
// isBlank(value)
//   Returns true if value only contains spaces
//-------------------------------------------------------------------
function isBlank(val){
	if(val==null){return true;}
	for(var i=0;i<val.length;i++) {
		if ((val.charAt(i)!=' ')&&(val.charAt(i)!="\t")&&(val.charAt(i)!="\n")&&(val.charAt(i)!="\r")){return false;}
		}
	return true;
	}

function y2k(number) { return (number < 1000) ? number + 1900 : number; }
function isDate (day,month,year) {
// checks if date passed is valid
// will accept dates in following format:
// isDate(dd,mm,ccyy), or
// isDate(dd,mm) - which defaults to the current year, or
// isDate(dd) - which defaults to the current month and year.
// Note, if passed the month must be between 1 and 12, and the
// year in ccyy format.

    var today = new Date();
    year = ((!year) ? y2k(today.getYear()):year);
    month = ((!month) ? today.getMonth():month-1);
    if (!day) return false
    var test = new Date(year,month,day);
    if ( (y2k(test.getYear()) == year) &&
         (month == test.getMonth()) &&
         (day == test.getDate()) )
        return true;
    else
        return false;
}

function echeck(str) {

	var at="@"
	var dot="."
	var lat=str.indexOf(at)
	var lstr=str.length
	var ldot=str.indexOf(dot)
	if (str.indexOf(at)==-1){
	   return false;
	}

	if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
	   return false;
	}

	if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
	    return false;
	}

	 if (str.indexOf(at,(lat+1))!=-1){
	    return false;
	 }

	 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
	    return false;
	 }

	 if (str.indexOf(dot,(lat+2))==-1){
	    return false;
	 }
	
	 if (str.indexOf(" ")!=-1){
	    return false;
	 }

		 return true;
}