LuaBase64编码：三字节转四字符的文本传输

local B64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
local function b64block(a, b, c)
    local n = a * 65536 + (b or 0) * 256 + (c or 0)
    local out = {}
    for i = 3, 0, -1 do
        local k = math.floor(n / 64 ^ i) % 64
        out[#out + 1] = B64:sub(k + 1, k + 1)
    end
    return table.concat(out)
end

local function b64encode(s)
    local out = {}
    for i = 1, #s, 3 do
        local a, b, c = s:byte(i, i + 2)
        local block = b64block(a, b, c)
        if not b then
            block = block:sub(1, 2) .. "=="
        elseif not c then
            block = block:sub(1, 3) .. "="
        end
        out[#out + 1] = block
    end
    return table.concat(out)
end
local p = getplayerbyname("b6401")
sendmsg(p, 1, b64encode("Man"))