/***************************by
garcon1986********************************/
<?php
//php avancé 5 example
$a = 'hello';
$a .= 'world';
$table = 'users';
$id = 5;
$sql = 'SELECT * from'.$table. "WHERE ID = '$id'";
//date() G显示24小时的格式，i显示分钟
echo 'il est'.date('G \h i').'il fait beau<p>';
// '=', '==', '===' 三者区别: '='是赋值，右边的值赋给左边；'=='是值相等，类型不一定等；'==='是恒等，值相等类型也相等；'!=='是值不等，或类型不等。
$a = '34';
$b = 34;
$a == $b;
//echo (boolean)($a == $b);
var_dump((bool) $a == $b);
echo '<br>';
$a === $b;
//echo (boolean)($a === $b);
var_dump((bool) $a === $b);
echo '<br>';
var_dump((bool)($a !== $b));
echo '<p>';
//arithmetic operator
echo 5*"", '<br>'; //0
echo 5+false, '<br>'; //5
echo 5/NULL, '<br>'; //Warning: Division by zero
//assignment operator
$a = ($b = 4) + 5; // $a 现在成了 9，而 $b 成了 4。
echo "$a,$b<br>";
$a = 3;
$a += 5; // sets $a to 8, as if we had said: $a = $a + 5;
$b = "Hello ";
$b .= "There!"; // sets $b to "Hello There!", just like $b = $b . "There!";
echo "$a,$b<br>";
//bitwise operator
echo 12 ^ 9; // 输出为 '5'
echo '<br>';
echo "12" ^ "9"; // 输出退格字符（ascii 8）
// ('1' (ascii 49)) ^ ('9' (ascii 57)) = #8
echo '<br>';
echo "hallo" ^ "hello"; // 输出 ascii 值 #0 #4 #0 #0 #0
echo '<p>'; // 'a' ^ 'e' = #4
/*
--------- --------- -- ---------
result value op test
--------- --------- -- ---------
Bitwise AND
( 0 = 0000) = ( 0 = 0000) & ( 5 = 0101)
( 1 = 0001) = ( 1 = 0001) & ( 5 = 0101)
( 0 = 0000) = ( 2 = 0010) & ( 5 = 0101)
( 4 = 0100) = ( 4 = 0100) & ( 5 = 0101)
( 0 = 0000) = ( 8 = 1000) & ( 5 = 0101)
Bitwise Inclusive OR
( 5 = 0101) = ( 0 = 0000) | ( 5 = 0101)
( 5 = 0101)
