bit operators in the PHP language &, |, ^, ~, 〈〈, 〉〉

"&" Bitwise AND operation

The bitwise AND operator "&" is the binocular operator. Its function is to participate in the operation of the two number of the corresponding binary phase. Only the corresponding two binaries are 1 o'clock, the result bit is 1, otherwise 0. The number of participating operations appears in a complementary fashion.

For example:9&5 can be written as follows:00001001 (9 twos complement) &00000101 (5 twos complement)00000001 (1 twos complement)<? 9 5; Echo sprintf ("%b", $a &$b); >

"|" Bitwise OR OPERATION

Bitwise OR operator ' | ' is the binocular operator. Its function is to participate in the operation of the two number of the corresponding binary phase or. As long as the corresponding two binary has one for 1 o'clock, the result bit is 1. The two numbers participating in the operation are in complement.

For example:9|5 The following can be written:00001001|00000101 00001101(decimal 13) Visible 9|5= -<?php$a=9; $b=5; Echo sprintf ("%b", $a | $b)."\ n";// BinaryEcho sprintf ("%d", $a | $b)."\ n";//decimal

"^" Bitwise XOR OR operation

The bitwise XOR operator "^" is the binocular operator. Its function is to participate in the operation of the two number of the corresponding binary dissimilarity or, when the two corresponding binary differences, the result is 1. Participation in the arithmetic is still in complement, for example 9^5 can be written as follows:

00001001^00000101 00001100(decimal)<?php$a=9; $b=5; Echo sprintf ("%b", $a ^ $b)."\ n";// BinaryEcho sprintf ("%d", $a ^ $b)."\ n";//decimal

"~" Negation operation

Negation operator ~ is a single-mesh operator with right-associative. Its function is to reverse the bitwise negation of the number of participating operations.

For example, the operation of the ~ (0000000000001001) Result:1111111111110110<? 95; Echo sprintf ("%b", ~ $a). " \ n " // Binary

"〈〈" left-shift operation

The left-shift operator "<<" is the binocular operator. Its function to the left of the "<<" operand of all the binary all left a number of bits, the "<<" to the right of the number to specify the number of bits moved, high drop, low 0.

For example, a<<4 refers to moving the binary of a to the Left 4 bits. such as a=00000011<? 3= $a <<4; Echo sprintf ("%d" , $temp). " \ n " // decimal

">>" right shift operation

The right-shift operator ">>" is the binocular operator. The function is to shift all the binary of the left operand of ">>" to the right of several bits, and the number to the right of ">>" to specify the number of bits to move.

For example: Set a= zero, a>>4 to move the 00110000 right to 00000011 (decimal 3). It should be stated that, for the signed number, when moving right, the symbol bit is moved along with it. When a positive number, the highest bit of 0, and negative, the sign bit is 1, the highest bit is 0 or a complement of 1 depends on the provisions of the compilation system < = $a >> 4, echo sprintf ("%d" , $temp). " \ n " // decimal

Bitwise operators in PHP (almost rarely used)