function_exists
Description
The function_exists of Function Handling for PHP return true if the given function has been defined.
Syntax
function_exists(
string $function
): boolParameters
function
The function name, as a string.
Return
Returns true if function exists and is a function, false otherwise.
NOTE: This function will return false for constructs, such as include_once and echo.
Examples
1 · function
<?
function myfunction()
{
}
$function = "myfunction";
$return = function_exists($function);
var_export($return);
true
2 · namespace
<?
namespace mynamespace;
function myfunction()
{
}
$function = __NAMESPACE__ . "\myfunction";
$return = function_exists($function);
var_export($return);
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