转换字母的大小写

eg1：  

private void buttonX1_Click(object sender, EventArgs e)
        {
            string test = "afsfsdf,sdfsfdsf,sdfdsfsdf,AFSFASF,adfsf,afdsf,,,,,";
            string firstUpper = toUpper(test);
            string uppers = firstUpper.Replace(",","");
            Console.WriteLine(test);//原始数据
            Console.WriteLine(uppers);//将首字母转换成大写，去除逗号
            Console.WriteLine(uppers.ToLower());//将字母全部转换为小写，去除逗号
            string result = test.Replace(",", " ");//将逗号转换为空格
            Console.WriteLine(result.Trim ().Replace(" ","_").ToLower()); //清空空格，将空格转换为下滑线

        }
 //将首字母转换成大写
        public static string toUpper(string text)
        {
            bool b = true;//逗号的下一位
            int charNum = 0;//第一位
            char[] strChar = text.ToCharArray();
            for (int i = 0; i < strChar.Length; i++)
            {
                charNum = (int)strChar[i];
                if (b && charNum > 96 && charNum < 123)
                {
                    strChar[i] = (char)(charNum - 32);//代表大小写相差32
                    b = false;
                    continue;
                }
                if (charNum == 44)//判断是否为逗号
                {
                    b = true;
                    continue;
                }
                b = false;
            }
            return new string(strChar);
        }

eg2：

 public static class TextTo
    {
        /// <summary>
        /// 单词首字母大写
        /// </summary>
        /// <param name="text">需要转换的文本</param>
        /// <param name="str">判定字符</param>
        /// <param name="isFirst">是否验证第一个字母</param>
        /// <returns>转换后的文本</returns>
        public static string ToUpper(string text, char str, bool isFirst)
        {
            bool b = isFirst;//设定字符的下一位
            int charNum = 0;//第一位
            char[] strChar = text.ToCharArray();
            for (int i = 0; i < strChar.Length; i++)
            {
                charNum = (int)strChar[i];
                if (b && charNum > 96 && charNum < 123)
                {
                    strChar[i] = (char)(charNum - 32);//代表大小写相差32
                    b = false;
                    continue;
                }
                if (strChar[i] == str)//判断是否为设定字符
                {
                    b = true;
                    continue;
                }
                b = false;
            }
            return new string(strChar);
        }
    }

 public class WordText
    {
        public WordText(string text)
        {
            if ((text = text.Trim().ToLower()).Length == 0)
            {
                return;
            }
            AllUp = TextTo.ToUpper(text, ',', true).Replace(",", "");
            FirstNoUp = AllUp.Substring(0, 1).ToLower() + AllUp.Substring(1);
            UnderlineText = text.Replace(',', '_');
        }
        public string AllUp
        {
            get;
            set;
        }

        public string FirstNoUp
        {
            get;
            set;
        }

        public string UnderlineText
        {
            get;
            set;
        }

    }