但是,如果标志是某个变量中的位,那么是哪个变量呢?
Message#c09be45f flags:# out:flags.1?true mentioned:flags.4?true media_unread:flags.5?true silent:flags.13?true post:flags.14?true id:int from_id:flags.8?int to_id:Peer fwd_from:flags.2?MessageFwdHeader via_bot_id:flags.11?int reply_to_msg_id:flags.3?int date:int message:string media:flags.9?MessageMedia reply_markup:flags.6?ReplyMarkup entities:flags.7?Vector<MessageEntity> views:flags.10?int edit_date:flags.15?int = Message;
Example: flags:# out:flags.1?true
解码标志: BinaryAND(flags, 2^ix) === 2^ix --> 这将帮助您确定是否包含某个字段
flags= 如果该值flags
字段,这通常是带有标志的对象的第一个字段
ix == 标志索引,这是一个指示标志位置的数字,例如out:flags.1?true
这里out是flag位置1的字段,类型为true
对于上面的例子out
将有一个值为true
if BAND(flags,2^N) == 2^N
否则,out
字段被忽略
代码 - 消息编码 (Elixir)
def encode(%Message{} = x), do: <<95, 228, 155, 192, encode(:Int, x.flags)::binary, enc_f(:True, x.out, x.flags, 2)::binary, enc_f(:True, x.mentioned, x.flags, 16)::binary, enc_f(:True, x.media_unread, x.flags, 32)::binary, enc_f(:True, x.silent, x.flags, 8192)::binary, enc_f(:True, x.post, x.flags, 16384)::binary, encode(:Int, x.id)::binary, enc_f(:Int, x.from_id, x.flags, 256)::binary, encode(x.to_id)::binary, enc_f(x.fwd_from, x.flags, 4)::binary, enc_f(:Int, x.via_bot_id, x.flags, 2048)::binary, enc_f(:Int, x.reply_to_msg_id, x.flags, 8)::binary, encode(:Int, x.date)::binary, encode(:String, x.message)::binary, enc_f(x.media, x.flags, 512)::binary, enc_f(x.reply_markup, x.flags, 64)::binary, enc_vf(x.entities, x.flags, 128)::binary, enc_f(:Int, x.views, x.flags, 1024)::binary, enc_f(:Int, x.edit_date, x.flags, 32768)::binary>>
代码 - 消息解码 (Elixir)
def decode(<<95, 228, 155, 192, bin::binary>>) do
{flags, bin} = decode(:Int, bin)
{out, bin} = decode(:True, bin, flags, 2) # 1
{mentioned, bin} = decode(:True, bin, flags, 16) # 4
{media_unread, bin} = decode(:True, bin, flags, 32) # 5
{silent, bin} = decode(:True, bin, flags, 8192) # 13
{post, bin} = decode(:True, bin, flags, 16384) # 14
{id, bin} = decode(:Int, bin)
{from_id, bin} = decode(:Int, bin, flags, 256) # 8
{to_id, bin} = decode(bin)
{fwd_from, bin} = decode(bin, flags, 4) # 2
{via_bot_id, bin} = decode(:Int, bin, flags, 2048) # 11
{reply_to_msg_id, bin} = decode(:Int, bin, flags, 8) # 3
{date, bin} = decode(:Int, bin)
{message, bin} = decode(:String, bin)
{media, bin} = decode(bin, flags, 512) # 9
{reply_markup, bin} = decode(bin, flags, 64) # 6
{entities, bin} = decode([:MessageEntity], bin, flags, 128) # 7
{views, bin} = decode(:Int, bin, flags, 1024) # 10
{edit_date, bin} = decode(:Int, bin, flags, 32768) # 15
{%Message{flags: flags, out: out, mentioned: mentioned, media_unread: media_unread, silent: silent, post: post, id: id, from_id: from_id, to_id: to_id, fwd_from: fwd_from, via_bot_id: via_bot_id, reply_to_msg_id: reply_to_msg_id, date: date, message: message, media: media, reply_markup: reply_markup, entities: entities, views: views, edit_date: edit_date}, bin}
end
#5 == 2^5 == 32
#4 == 2^4 == 16
所以基本上N == 2^N, where N == ix