字符串换行控制代码片段

    /// <summary>
    /// 格式化字符串，按指定长度添加换行，如果本身有换行则看每一个换行的长度，如有超出加换行
    /// </summary>
    /// <param name="str"></param>
    /// <param name="lineMaxCharCount"></param>
    /// <returns></returns>
    private string FormatString(String str,int lineMaxCharCount)
    {
        if (string.IsNullOrEmpty(str))
        {
            return string.Empty;
        }
        StringBuilder newStr = new StringBuilder();
        if (str.Contains("\r\n"))
        {
            String[] newStrs = str.Split(new string[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries);
            foreach (String item in newStrs)
            {
                if (item.Length > lineMaxCharCount)
                {
                    int count = item.Length / lineMaxCharCount;
                    for (int i = 1; i < count + 1; i++)
                    {
                        newStr.Append(item.Insert(lineMaxCharCount * i + (i - 1) * 2, "\r\n"));
                    }
                    newStr.Append("\r\n");
                }
                else
                {
                    newStr.Append(item + "\r\n");
                }
            }
            return newStr.ToString();
        }
        else
        {
            int len = str.Length;
            if (len > lineMaxCharCount)
            {
                int count = len / lineMaxCharCount;
                for (int i = 1; i < count + 1; i++)
                {
                    str = str.Insert(lineMaxCharCount * i + (i - 1) * 2, "\r\n");
                }
                str = str + "\r\n";
            }
            return str;
        }
    }