摘要：
///////////////publicstringToBase64Str(stringStr){byte[]b=System.Text.Encoding.Default.GetBytes(Str);returnConvert.ToBase64String(b);}///
/// <summary>
///
/// </summary>
/// <param name="Str"></param>
/// <returns></returns>
public string ToBase64Str(string Str)
{
byte[] b = System.Text.Encoding.Default.GetBytes(Str);
return Convert.ToBase64String(b);
}
/// <summary>
///
/// </summary>
/// <param name="Str"></param>
/// <returns></returns>
public string FromBase64Str(String Str)
{
byte[] b = Convert.FromBase64String(Str);
return System.Text.Encoding.Default.GetString(b);
}