PHP function usage method and function definition method_PHP tutorial

The syntax for a function is:
Function definition method

Copy code The code is as follows:

function "function_name" ( arg1, arg2...)
{
[code to execute]
return [final_result];
}

where [final_result] is usually a variable returned from a function value.
Let’s see an example

Copy the code The code is as follows:

function double_this_number($input_number)
{
return $input_number*2;
}

Call method

Copy code The code is as follows:

$x = 10;
$y = double_this_number($x);
print $y;

The output value is
10
Good , let’s look at a more complicated function usage method

Copy code The code is as follows:

function safePost($v=0 )
{
if( $v==0 )
{
$protected = array("_GET", "_POST", "_SERVER", "_COOKIE", "_FILES", "_ENV ", "GLOBALS");
foreach($protected as $var) {
if(isset($_REQUEST[$var]) || isset($_FILES[$var]))
{
die("Access denied");
}
}
}
}

Call method
safePost();
This is optional Define parameters, because $v==0 is set with a parameter by default, which is very helpful for function expansion.

http://www.bkjia.com/PHPjc/321825.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/321825.htmlTechArticleThe syntax for a function is: Function definition method copy code The code is as follows: function "function_name" (arg1, arg2. ..) { [code to execute] return [final_result]; } where [final_re...