C# 大小写转换合集

        private static readonly String cnNumber = "零壹贰叁肆伍陆柒捌玖";
        private static readonly String cnUnit = "分角元拾佰仟万拾佰仟亿拾佰仟兆拾佰仟";

1.在代码中以 Excel 加日期的算法

  /// <summary>/// 传入原日期和所加月数，按照excel加月数算法，返回新日期/// Excel计算方式和C#的计算方式不一致/// C#的计算方式：若新日期超出了此月的最大日期数，比如9月31日，新日期为该月的最后一天9月30日/// Excel的算法： 若新日期超出了此月的最大日期数，比如9月31日，新日期为该月最后一日延后超出的天数即是10月1日/// </summary>/// <param name="old_date">原日期</param>/// <param name="monthNum">所加的月数</param>/// <returns>新的日期</returns>public static DateTime Excel计算日期(DateTime old_date, int monthNum){int day = old_date.Day;DateTime new_date = DateTime.Now;new_date = old_date.AddMonths(monthNum);switch (day){case 29:if (!DateTime.IsLeapYear(new_date.Year) && new_date.Month == 2 && new_date.Day == 28){new_date = new_date.AddDays(1);}break;case 30:if (new_date.Month == 2){if (DateTime.IsLeapYear(new_date.Year)){if (new_date.Month == 2 && new_date.Day == 29){new_date = new_date.AddDays(1);}}else{if (new_date.Month == 2 && new_date.Day == 28){new_date = new_date.AddDays(1);}}}break;case 31:if (new_date.Day == 30){if (new int[] { 4, 6, 9, 11 }.Contains(new_date.Month)){new_date = new_date.AddDays(1);}}else if (new_date.Day == 29){if (DateTime.IsLeapYear(new_date.Year)){new_date = new_date.AddDays(1);}}else if (new_date.Day == 28){if (!DateTime.IsLeapYear(new_date.Year)){new_date = new_date.AddDays(1);}}break;default:break;}return new_date;}

2.数字转大写

        /// <summary>/// 数字转化为大写/// </summary>/// <param name="num"></param>/// <returns></returns>public static string numtoUpper(int num){String str = num.ToString();string rstr = "";int n;for (int i = 0; i < str.Length; i++){n = Convert.ToInt16(str[i].ToString());//char转数字,转换为字符串，再转数字switch (n){case 0: rstr = rstr + "〇"; break;case 1: rstr = rstr + "一"; break;case 2: rstr = rstr + "二"; break;case 3: rstr = rstr + "三"; break;case 4: rstr = rstr + "四"; break;case 5: rstr = rstr + "五"; break;case 6: rstr = rstr + "六"; break;case 7: rstr = rstr + "七"; break;case 8: rstr = rstr + "八"; break;default: rstr = rstr + "九"; break;}}return rstr;}

3.日、月、日期转大写

        //月转化为大写public static string monthtoUpper(int month){if (month < 10){return numtoUpper(month);}elseif (month == 10) { return "十"; }else{return "十" + numtoUpper(month - 10);}}//日转化为大写public static string daytoUpper(int day){if (day < 20){return monthtoUpper(day);}else{String str = day.ToString();if (str[1] == '0'){return numtoUpper(Convert.ToInt16(str[0].ToString())) + "十";}else{return numtoUpper(Convert.ToInt16(str[0].ToString())) + "十"+ numtoUpper(Convert.ToInt16(str[1].ToString()));}}}//日期转换为大写public static string dateToUpper(System.DateTime date){int year = date.Year;int month = date.Month;int day = date.Day;return numtoUpper(year) + "年" + monthtoUpper(month) + "月" + daytoUpper(day) + "日";}

4.人民币金额小写转大写

        /// <summary> /// 转换人民币大小金额 /// </summary> /// <param name="num">金额</param> /// <returns>返回大写形式</returns> public static string GetUpper(decimal num){String[] tmpString = num.ToString().Split('.');String intString = num.ToString();   // 默认为整数String decString = "";            // 保存小数部分字串String rmbCapital = "";            // 保存中文大写字串int k;int j;int n;if (tmpString.Length > 1){intString = tmpString[0];             // 取整数部分decString = tmpString[1];             // 取小数部分}decString += "00";decString = decString.Substring(0, 2);   // 保留两位小数位intString += decString;try{k = intString.Length - 1;if (k > 0 && k < 18){for (int i = 0; i <= k; i++){j = (int)intString[i] - 48;// rmbCapital = rmbCapital + cnNumber[j] + cnUnit[k-i];     // 供调试用的直接转换n = i + 1 >= k ? (int)intString[k] - 48 : (int)intString[i + 1] - 48; // 等效于 if( ){ }else{ }if (j == 0){if (k - i == 2 || k - i == 6 || k - i == 10 || k - i == 14){rmbCapital += cnUnit[k - i];}else{if (n != 0){rmbCapital += cnNumber[j];}}}else{rmbCapital = rmbCapital + cnNumber[j] + cnUnit[k - i];}}rmbCapital = rmbCapital.Replace("兆亿万", "兆");rmbCapital = rmbCapital.Replace("兆亿", "兆");rmbCapital = rmbCapital.Replace("亿万", "亿");rmbCapital = rmbCapital.TrimStart('元');rmbCapital = rmbCapital.TrimStart('零');string lastStr = rmbCapital.Substring(rmbCapital.Length - 1);if (lastStr == "元" || lastStr == "角")rmbCapital += "整";return rmbCapital;}else{return "";   // 超出转换范围时，返回零长字串}}catch{return "";   // 含有非数值字符时，返回零长字串}}

5.获取中文字拼音首字母

        /// <summary>/// 获取中文拼音首字母/// </summary>/// <param name="ChineseStr">中文字符串</param>/// <param name="ToUpper">是否转化为大写</param>/// <returns></returns>public static string GetSpellCode(string ChineseStr, bool ToUpper = true){string Capstr = string.Empty;byte[] ZW = new byte[2];long ChineseStr_int;string CharStr, ChinaStr = "";for (int i = 0; i <= ChineseStr.Length - 1; i++){CharStr = ChineseStr.Substring(i, 1).ToString();ZW = System.Text.Encoding.Default.GetBytes(CharStr);// 得到汉字符的字节数组if (ZW.Length == 1){ChinaStr = CutString(CharStr.ToUpper(), 1);}else{int i1 = (short)(ZW[0]);int i2 = (short)(ZW[1]);ChineseStr_int = i1 * 256 + i2;if ((ChineseStr_int >= 45217) && (ChineseStr_int <= 45252)) { ChinaStr = "a"; }else if ((ChineseStr_int >= 45253) && (ChineseStr_int <= 45760)) { ChinaStr = "b"; }else if ((ChineseStr_int >= 45761) && (ChineseStr_int <= 46317)) { ChinaStr = "c"; }else if ((ChineseStr_int >= 46318) && (ChineseStr_int <= 46825)) { ChinaStr = "d"; }else if ((ChineseStr_int >= 46826) && (ChineseStr_int <= 47009)) { ChinaStr = "e"; }else if ((ChineseStr_int >= 47010) && (ChineseStr_int <= 47296)) { ChinaStr = "f"; }else if ((ChineseStr_int >= 47297) && (ChineseStr_int <= 47613)) { ChinaStr = "g"; }else if ((ChineseStr_int >= 47614) && (ChineseStr_int <= 48118)) { ChinaStr = "h"; }else if ((ChineseStr_int >= 48119) && (ChineseStr_int <= 49061)) { ChinaStr = "j"; }else if ((ChineseStr_int >= 49062) && (ChineseStr_int <= 49323)) { ChinaStr = "k"; }else if ((ChineseStr_int >= 49324) && (ChineseStr_int <= 49895)) { ChinaStr = "l"; }else if ((ChineseStr_int >= 49896) && (ChineseStr_int <= 50370)) { ChinaStr = "m"; }else if ((ChineseStr_int >= 50371) && (ChineseStr_int <= 50613)) { ChinaStr = "n"; }else if ((ChineseStr_int >= 50614) && (ChineseStr_int <= 50621)) { ChinaStr = "o"; }else if ((ChineseStr_int >= 50622) && (ChineseStr_int <= 50905)) { ChinaStr = "p"; }else if ((ChineseStr_int >= 50906) && (ChineseStr_int <= 51386)) { ChinaStr = "q"; }else if ((ChineseStr_int >= 51387) && (ChineseStr_int <= 51445)) { ChinaStr = "r"; }else if ((ChineseStr_int >= 51446) && (ChineseStr_int <= 52217)) { ChinaStr = "s"; }else if ((ChineseStr_int >= 52218) && (ChineseStr_int <= 52697)) { ChinaStr = "t"; }else if ((ChineseStr_int >= 52698) && (ChineseStr_int <= 52979)) { ChinaStr = "w"; }else if ((ChineseStr_int >= 52980) && (ChineseStr_int <= 53640)) { ChinaStr = "x"; }else if ((ChineseStr_int >= 53689) && (ChineseStr_int <= 54480)) { ChinaStr = "y"; }else if ((ChineseStr_int >= 54481) && (ChineseStr_int <= 55289)) { ChinaStr = "z"; }else { ChinaStr = CharStr; }}Capstr += ChinaStr;}Capstr = Capstr.Replace("昊", "h").Replace("丞", "c").Replace("鑫", "x").Replace("蕲", "Q");return ToUpper ? Capstr.ToUpper() : Capstr.ToLower();}

6.银行卡号设置4位加空格

        /// <summary>/// 银行卡每四位加空格/// </summary>/// <param name="Card">银行卡号</param>/// <returns></returns>public static string 处理银行卡号(string Card){if (String.IsNullOrEmpty(Card))return "";Card = Card.Replace(" ","");           return Regex.Replace(Card, @"(\d{4}(?!$))", "$1 ");}