Ключевые слова PHP
Ключевые слова PHP
PHP имеет набор ключевых слов, которые являются зарезервированными словами, которые нельзя использовать в качестве имен функций, имен классов или имен методов. До PHP 7 эти ключевые слова также нельзя было использовать в качестве имен свойств класса:
Keyword | Description |
---|---|
abstract | Declare a class as abstract |
and | A logical operator |
as | Used in the foreach loop |
break | Break out of loops and switch statements |
callable | A data type which can be executed as a function |
case | Used in the switch conditional |
catch | Used in the try..catch statement |
class | Declare a class |
clone | Create a copy of an object |
const | Define a class constant |
continue | Jump to the next iteration of a loop |
declare | Set directives for a block of code |
default | Used in the switch statement |
do | Create a do...while loop |
echo | Output text |
else | Used in conditional statements |
elseif | Used in conditional statements |
empty | Check if an expression is empty |
enddeclare | End a declare block |
endfor | End a for block |
endforeach | End a foreach block |
endif | End an if or elseif block |
endswitch | End a switch block |
endwhile | End a while block |
extends | Extends a class or interface |
final | Declare a class, property or method as final |
finally | Used in the try...catch statement |
fn | Declare an arrow function |
for | Create a for loop |
foreach | Create a foreach loop |
function | Create a function |
global | Import variables from the global scope |
goto | Jump to a line of code |
if | Create a conditional statement |
implements | Implement an interface |
include | Embed code from another file |
include_once | Embed code from another file |
instanceof | Test an object's class |
insteadof | Resolve conflicts with traits |
interface | Declare an interface |
isset | Check if a variable exists and is not null |
list | Assigns array elements into variables |
namespace | Declares a namespace |
new | Creates an object |
or | A logical operator |
Output text | |
private | Declare a property, method or constant as private |
protected | Declare a property, method or constant as protected |
public | Declare a property, method or constant as public |
require | Embed code from another file |
require_once | Embed code from another file |
return | Exit a function and return a value |
static | Declare a property or method as static |
switch | Create a switch block |
throw | Throw an exception |
trait | Declare a trait |
try | Create a try...catch structure |
unset | Delete a variable or array element |
use | Use a namespace |
var | Declare a variable |
while | Create a while loop or end a do...while loop |
xor | A logical operator |
yield | Used in generator functions |
yield from | Used in generator functions |