Lua 5.1 位操作（與，或，異或操作）

由於lua5.1不支持位操作，自己寫了一個lua的位操作函數，代碼如下：

方法1：

function Xor(num1,num2)
    local tmp1 = num1
    local tmp2 = num2
    local str = ""
    repeat
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 == s2 then
            str = "0"..str
        else
            str = "1"..str
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
    until(tmp1 == 0 and tmp2 == 0)
    return tonumber(str,2)
end
 
function And(num1,num2)
    local tmp1 = num1
    local tmp2 = num2
    local str = ""
    repeat
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 == s2 then
            if s1 == 1 then
                str = "1"..str
            else
                str = "0"..str
            end
        else
            str = "0"..str
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
    until(tmp1 == 0 and tmp2 == 0)
    return tonumber(str,2)
end
 
function Or(num1,num2)
    local tmp1 = num1
    local tmp2 = num2
    local str = ""
    repeat 
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 == s2 then
            if s1 == 0 then
                str = "0"..str
            else
                str = "1"..str
            end
        else
            str = "1"..str
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
    until(tmp1 == 0 and tmp2 == 0)
    return tonumber(str,2)
end

使用方法如下：

local tmp1 = 0x52
local tmp2 = 0x01
 
print(Xor(tmp1,tmp2))  --輸出tmp1 異或 tmp2 的操作結果
print(And(tmp1,tmp2))    --輸出tmp1 與 tmp2 的操作結果
print(Or(tmp1,tmp2))    --輸出tmp1 或 tmp2 的操作結果

 

加入支持負數的位運算操作： 但是負數和負數位操作出來的顯示是個整數

如 And(-8,-5)    結果 ：4294967288  在32位機器上就是 -8

function checkNums( nums )
    local n = nums
    if n >= 0 then
        return n
    else
        n = 0 - n
        n = 0xffffffff - n + 1
    end
    return n
end
function resultCover( n )
    local  num = n
    if num >= 0x80000000 then
        num = num - 0xffffffff - 1
    end
    return num
end
 
function And(num1,num2)
    local tmp1 = checkNums(num1)
    local tmp2 = checkNums(num2)
    local ret = 0
    local count = 0
    repeat
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 == s2 and s1 == 1 then
            ret = ret + 2^count
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
        count = count + 1
    until(tmp1 == 0 and tmp2 == 0)
    return resultCover(ret)
end
 
function Or(num1,num2)
    local tmp1 = checkNums(num1)
    local tmp2 = checkNums(num2)
    local ret = 0
    local count = 0
    repeat
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 == s2 and s1 == 0 then
 
        else
            ret = ret + 2^count
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
        count = count + 1
    until(tmp1 == 0 and tmp2 == 0)
    return resultCover(ret)
end
 
 
function Xor(num1,num2)
    local tmp1 = checkNums(num1)
    local tmp2 = checkNums(num2)
    local ret = 0
    local count = 0
    repeat
        local s1 = tmp1 % 2
        local s2 = tmp2 % 2
        if s1 ~= s2 then
            ret = ret + 2^count
        end
        tmp1 = math.modf(tmp1/2)
        tmp2 = math.modf(tmp2/2)
        count = count + 1
    until(tmp1 == 0 and tmp2 == 0)
    return resultCover(ret)
end

5.3開始自帶位操作：

&    按位與
|    按位或
~    按位異或
>>    右移
<<    左移
~    按位非
使用方法：
c = a & b      
c = a | b
c = a ~ b
c = a >> b
c = a << b
c = ~a

https://blog.csdn.net/u013625451/article/details/84644839