C#实现将32位MD5摘要串转换为128位二进制字符串的方法

/// <summary>/// 将字符串转成二进制/// </summary>/// <param name="s">源字符串</param>/// <returns>二进制串</returns>internal static string ConvertStringToBinary(string s){  if (s.IsNullOrWhiteSpace())  {    throw new ArgumentNullException("源字符串为空", s);  }  if (s.Length != 32)  {    throw new ArgumentNullException("源字符串长度无效", s);  }  var bitBuilder = new StringBuilder(128);  for (var i = 0; i < s.Length; i += 2)  {    var tem = Convert.ToInt32(s.Substring(i, 2), 16);    bitBuilder.Append(Convert.ToString(tem, 2).PadLeft(8, '0'));  }  return bitBuilder.ToString();}