C# 控制显示的字符串的长度

public string StrName(object o,int length)
{
        if (o != null)
        {
            string content = o.ToString();
            Encoding encoding = Encoding.GetEncoding("gb2312");
            StringBuilder sb = new StringBuilder();
            int totalLength = 0;
            foreach (char contentChar in content)
            {
                int size = encoding.GetByteCount(new char[] { contentChar });
                if (totalLength + size > length - 2)
                {
                    sb.Append("....");
                    break;
                }
                sb.Append(contentChar);
                totalLength += size;
            }
            return sb.ToString();
        }
        else
            return null;
}

方法不止一个，仅供参考(这句话也是抄的.....)