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PHP 运算符

算数运算符

算数运算符是在PHP之中出现最多从运算符,术语二元运算符,主要对两个变量将进行操作,在PHP之中,主要分为六种基本算数运算符,分别为加(+)、减(-)、乘(*)、除(/)、取模(%)、曲负(-)

加法 (+)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a + $b;
echo "$one";
?>
</body>
</html>
减法 (-)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a - $b;
echo "$one";
?>
</body>
</html>
乘法 (*)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a * $b;
echo "$one";
?>
</body>
</html>
除法 (/)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a / $b;
echo "$one";
?>
</body>
</html>
取模(%)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a % $b;
echo "$one";
?>
</body>
</html>
取负 (-)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = -$b;
echo "$one";
?>
</body>
</html>

赋值运算符

赋值运算符可被理解为将右边的值赋给左边的变量,如$one = $a+$b,则标识将$a、$b赋值给了$one:

例子
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a + $b;
echo "$one";
?>
</body>
</html>
同等于加法
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a + 10; // 同等与 1 + 10
echo "$one";
?>
</body>
</html>
同等与除法
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 1;
$b = 3;
$one = $a / 0.5;
echo "$one";
?>
</body>
</html>

递增/递减运算符

前递增
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$one = 1;
$three = ++$one;
echo "$three";
?>
</body>
</html>
前递减
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$one = 1;
$three = --$one;
echo "$three";
?>
</body>
</html>

递增递减运算符表

ID DA FA
++$a $a 前增加1 递增
$a++ $a 后增加1
–$a $a 前递减 递减
$a– $a 后递减

比较运算符

相等 (==)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$one = 10;
$two = 10;
if ($one == $two) {
echo "\$one相等于\$two";
}
?>
</body>
</html>
不相等于 (!=)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$one = 10;
$two = 110;
if ($one != $two) {
echo "\$one不相等于\$two";
}
?>
</body>
</html>
ID DA FA
== 等于 等于
=== 完全相等
!= 不等于 不等于
<> 不等于
!== 非全等
< 小于 大于小于
> 小于
>= 大于或等于 小于/大于等于
<= 小于或等于
|| 判断是否取值 取值

逻辑运算符

逻辑运算符于上述不同的是它可以操作布尔类型数据,在PHP中逻辑运算符一共有六种,如下:

与 (and | &&)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 10;
$b = 10;
if ($a == 10 and $b == 10) {
echo "\$a 与 \$b 都为10";
}
?>
</body>
</html>

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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 10;
$b = 10;
if ($a == 10 && $b == 10) {
echo "\$a 与 \$b 都为10";
}
?>
</body>
</html>
或 (or | xor | || )
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 10;
$b = 110;
if ($a == 10 or $b == 1) {
echo "10或1,都能看到";
}
?>
</body>
</html>

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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 10;
$b = 110;
if ($a == 10 xor $b == 1) {
echo "10或1,都能看到";
}
?>
</body>
</html>

再或者

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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 10;
$b = 110;
if ($a == 10 || $b == 1) {
echo "10或1,都能看到";
}
?>
</body>
</html>
非 (!)
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>demo</title>
</head>
<body>
<?php
$a = 11;
if ($a !== 10) {
echo "如果\$为10,则不显示";
}
?>
</body>
</html>
ID DA FA
and
&& 与($a 与 $b 都为10)
or 或者
xor 异或(10或1,都能看到)
|| 或(10或1,都能看到)
! 非(如果$为10,则不显示)
as 如同 如同
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