Convert dates to uppercase and lowercase

//usage Mode Numtoupper ("2014") + "year" + Monthtoupper ("12") + "month" + daytoupper ("12") + "Day"     Public Static stringNumtoupper (intnum) {String str=Num.            ToString (); stringRSTR =""; intN;  for(inti =0; I < Str. Length; i++) {n= Convert.ToInt16 (Str[i]. ToString ());//Char to a number, converted to a string, then to a number                Switch(n) { Case 0: RSTR = rstr +"0"; Break;  Case 1: RSTR = rstr +"a"; Break;  Case 2: RSTR = rstr +"two"; Break;  Case 3: RSTR = rstr +"three"; Break;  Case 4: RSTR = rstr +"Four"; Break;  Case 5: RSTR = rstr +"Five"; Break;  Case 6: RSTR = rstr +"Six"; Break;  Case 7: RSTR = rstr +"Seven"; Break;  Case 8: RSTR = rstr +"Eight"; Break; default: RSTR = rstr +"Nine"; Break; }            }            returnRstr; }        //convert Month to uppercase         Public Static stringMonthtoupper (intmonth) {            if(Month <Ten)            {                returnNumtoupper (month); }            Else                if(Month = =Ten) {return "10"; } Else                {                    return "10"+ numtoupper (Month-Ten); }        }        //convert Day to uppercase         Public Static stringDaytoupper (intDay ) {            if(Day < -)            {                returnMonthtoupper (day); }            Else{String str=Day .                ToString (); if(str[1] =='0')                {                    returnNumtoupper (Convert.ToInt16 (str[0]. ToString ())) +"10"; }                Else                {                    returnNumtoupper (Convert.ToInt16 (str[0]. ToString ())) +"10"+ Numtoupper (convert.toint16 (str[1].                ToString ())); }            }        }        //convert date to uppercase        Private stringdatetoupper (system.datetime date) {//by Len Lei email:[email protected],[email protected] 2007.10.25            intYear =date.            year; intmonth =date.            Month; intDay =date.            Day; returnNumtoupper (year) +"years"+ monthtoupper (Month) +"Month"+ Daytoupper (Day) +"Day"; }

Convert dates to uppercase and lowercase