protected bool  IsChineseLetter(string input,int index){    int code = 0;    int chfrom = Convert.ToInt32("4e00", 16);  //范圍（0x4e00～0x9fff）轉(zhuǎn)換成int（chfrom～chend）    int chend = Convert.ToInt32("9fff", 16);    if (input != "")    {       code = Char.ConvertToUtf32(input, index);  //獲得字符串input中指定索引index處字符unicode編碼      if (code >= chfrom && code <= chend)      {         return true;   //當(dāng)code在中文范圍內(nèi)返回true       }      else      {         return false ;  //當(dāng)code不在中文范圍內(nèi)返回false       }     }     return false;}

public bool IsChina(string CString){   bool BoolValue = false;   for (int i = 0; i < CString.Length; i++)   {     if (Convert.ToInt32(Convert.ToChar(CString.Substring(i, 1))) < Convert.ToInt32(Convert.ToChar(128)))     {       BoolValue = false;     }     else     {       return BoolValue = true;     }   }   return BoolValue;}

/// <summary>/// 判斷句子中是否含有中文   寧夏大學(xué) 張冬 zd4004.blog.163.com/// </summary>/// <param >字符串</param>public bool WordsIScn(string words){  string TmmP;  for (int i = 0; i < words.Length; i++)  {    TmmP = words.Substring(i, 1);    byte[] sarr = System.Text.Encoding.GetEncoding("gb2312").GetBytes(TmmP);    if (sarr.Length == 2)    {      return true;    }  }  return false;}

for (int i=0; i<s.length; i++){Regex rx = new Regex("^[/u4e00-/u9fa5]$");if (rx.IsMatch(s[i]))// 是else// 否}

unicodeencoding unicodeencoding = new unicodeencoding();byte [] unicodebytearray = unicodeencoding.getbytes( inputstring );for( int i = 0; i < unicodebytearray.length; i++ ){i++;//如果是中文字符那么高位不為0if ( unicodebytearray[i] != 0 ){}……

/// <summary>/// 給定一個(gè)字符串，判斷其是否只包含有漢字/// </summary>/// <param name="testStr"></param>/// <returns></returns>public bool IsOnlyContainsChinese(string testStr){  char[] words = testStr.ToCharArray();  foreach (char word in words)  {    if ( IsGBCode(word.ToString()) || IsGBKCode(word.ToString()) ) // it is a GB2312 or GBK chinese word    {      continue;    }    else    {      return false;    }  }  return true;}/// <summary>/// 判斷一個(gè)word是否為GB2312編碼的漢字/// </summary>/// <param name="word"></param>/// <returns></returns>private bool IsGBCode(string word){  byte[] bytes = Encoding.GetEncoding("GB2312").GetBytes(word);  if (bytes.Length <= 1) // if there is only one byte, it is ASCII code or other code  {    return false;  }  else  {    byte byte1 = bytes[0];    byte byte2 = bytes[1];    if (byte1 >= 176 && byte1 <= 247 && byte2 >= 160 && byte2 <= 254)  //判斷是否是GB2312    {      return true;    }    else    {      return false;    }  }}/// <summary>/// 判斷一個(gè)word是否為GBK編碼的漢字/// </summary>/// <param name="word"></param>/// <returns></returns>private bool IsGBKCode(string word){  byte[] bytes = Encoding.GetEncoding("GBK").GetBytes(word.ToString());  if (bytes.Length <= 1) // if there is only one byte, it is ASCII code  {    return false;  }  else  {    byte byte1 = bytes[0];    byte byte2 = bytes[1];    if ( byte1 >= 129 && byte1 <= 254 && byte2 >= 64 && byte2 <= 254)   //判斷是否是GBK編碼    {      return true;    }    else    {      return false;    }  }}/// <summary>/// 判斷一個(gè)word是否為Big5編碼的漢字/// </summary>/// <param name="word"></param>/// <returns></returns>private bool IsBig5Code(string word){  byte[] bytes = Encoding.GetEncoding("Big5").GetBytes(word.ToString());  if (bytes.Length <= 1) // if there is only one byte, it is ASCII code  {    return false;  }  else  {    byte byte1 = bytes[0];    byte byte2 = bytes[1];    if ( (byte1 >= 129 && byte1 <= 254) && ((byte2 >= 64 && byte2 <= 126) || (byte2 >= 161 && byte2 <= 254)) )   //判斷是否是Big5編碼    {      return true;    }    else    {      return false;    }  }}