阿尼

public static string SetupType(string text) {
    //先去除換行字元
    text = text.Replace("\r", "").Replace("\n", "");

    //每行最大 Byte 數
    int bytesCountEachLine = 100;

    //記錄目前已處理完成的字元數
    int charIndex = 0;

    //最後的回傳值
    string result = string.Empty;

    Encoding ansi = Encoding.Default;
    byte[] textBytes = ansi.GetBytes(text);

    while (charIndex < text.Length) {
        //起始位置
        int start = ansi.GetByteCount(text.Substring(0, charIndex)) ;

        //利用 Encoding.GetCharCount 從起始位置將 100 個 Bytes 的字元一次取出
        int count = 0;

        if (textBytes.Length - start > bytesCountEachLine)
            count = ansi.GetCharCount(textBytes, start, bytesCountEachLine);
        else
            count = ansi.GetCharCount(textBytes, start, textBytes.Length - start);

        string target = text.Substring(charIndex, count);

        //取出來的字串可能會大於 100 Bytes，所以需要把多餘的去掉
        while (ansi.GetByteCount(target) > bytesCountEachLine) {
            target = target.Substring(0, target.Length - 1);
            count -= 1;
        }

        charIndex += count;


        //最後一行不用加斷行符號
        if (charIndex < text.Length)
            result += target + "\r\n";
        else
            result += target;
    }

    return result;
}