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PHP 运算符
2021-07-22 07:28:58 深夜i     --     --
P H P


PHP 运算符

运算符用于对变量和值执行操作。

PHP 将运算符分为以下几组:

  • 算术运算符
  • 赋值运算符
  • 比较运算符
  • 自增/自减运算符
  • 逻辑运算符
  • 字符串运算符
  • 数组运算符
  • 条件赋值运算符

PHP 算术运算符

PHP 算术运算符与数值一起使用以执行常见的算术运算, 如加法、减法、乘法等。

Operator Name Example Result Show it
+ Addition $x + $y Sum of $x and $y  
- Subtraction $x - $y Difference of $x and $y  
* Multiplication $x * $y Product of $x and $y  
/ Division $x / $y Quotient of $x and $y  
% Modulus $x % $y Remainder of $x divided by $y  
** Exponentiation $x ** $y Result of raising $x to the $y'th power  

PHP 赋值运算符

PHP 赋值运算符与数值一起使用以将值写入变量。

PHP 中的基本赋值运算符是“=”。 这意味着左操作数 被设置为右侧赋值表达式的值。

Assignment Same as... Description Show it
x = y x = y The left operand gets set to the value of the expression on the right  
x += y x = x + y Addition  
x -= y x = x - y Subtraction  
x *= y x = x * y Multiplication  
x /= y x = x / y Division  
x %= y x = x % y Modulus  

 


PHP 比较运算符

PHP 比较运算符用于比较两个值(数字或字符串):

Operator Name Example Result Show it
== Equal $x == $y Returns true if $x is equal to $y  
=== Identical $x === $y Returns true if $x is equal to $y, and they are of the same type  
!= Not equal $x != $y Returns true if $x is not equal to $y  
<> Not equal $x <> $y Returns true if $x is not equal to $y  
!== Not identical $x !== $y Returns true if $x is not equal to $y, or they are not of the same type  
> Greater than $x > $y Returns true if $x is greater than $y  
< Less than $x < $y Returns true if $x is less than $y  
>= Greater than or equal to $x >= $y Returns true if $x is greater than or equal to $y  
<= Less than or equal to $x <= $y Returns true if $x is less than or equal to $y  
<=> Spaceship $x <=> $y Returns an integer less than, equal to, or greater than zero, depending on if $x is less than, equal to, or greater than $y. Introduced in PHP 7.  

PHP 自增/自减运算符

PHP 递增运算符用于递增变量的值。

PHP 递减运算符用于递减变量的值。

Operator Name Description Show it
++$x Pre-increment Increments $x by one, then returns $x  
$x++ Post-increment Returns $x, then increments $x by one  
--$x Pre-decrement Decrements $x by one, then returns $x  
$x-- Post-decrement Returns $x, then decrements $x by one  

PHP 逻辑运算符

PHP 逻辑运算符用于组合条件语句。

Operator Name Example Result Show it
and And $x and $y True if both $x and $y are true  
or Or $x or $y True if either $x or $y is true  
xor Xor $x xor $y True if either $x or $y is true, but not both  
&& And $x && $y True if both $x and $y are true  
|| Or $x || $y True if either $x or $y is true  
! Not !$x True if $x is not true  

PHP 字符串运算符

PHP 有两个专门为字符串设计的运算符。

Operator Name Example Result Show it
. Concatenation $txt1 . $txt2 Concatenation of $txt1 and $txt2  
.= Concatenation assignment $txt1 .= $txt2 Appends $txt2 to $txt1  

PHP 数组运算符

PHP 数组运算符用于比较数组。

Operator Name Example Result Show it
+ Union $x + $y Union of $x and $y  
== Equality $x == $y Returns true if $x and $y have the same key/value pairs  
=== Identity $x === $y Returns true if $x and $y have the same key/value pairs in the same order and of the same types  
!= Inequality $x != $y Returns true if $x is not equal to $y  
<> Inequality $x <> $y Returns true if $x is not equal to $y  
!== Non-identity $x !== $y Returns true if $x is not identical to $y  

PHP 条件赋值运算符

PHP 条件赋值运算符用于根据条件设置值:

Operator Name Example Result Show it
?: Ternary $x = expr1 ? expr2 : expr3 Returns the value of $x.
The value of $x is expr2 if expr1 = TRUE.
The value of $x is expr3 if expr1 = FALSE
 
?? Null coalescing $x = expr1 ?? expr2 Returns the value of $x.
The value of $x is expr1 if expr1 exists, and is not NULL.
If expr1 does not exist, or is NULL, the value of $x is expr2.
Introduced in PHP 7
 

PHP 练习

通过练习测试自己

锻炼:

10乘以5,输出结果。

echo 10  5;

 

 

 

  
  
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