如何从地址栏调用php函数？

how can i call function declared in my php file from address bar? I already tried appending function name with site address but it didn't called the function..

http://myWebSite.com/myFile.php?writeMessage

myfile.php:

<?php
  /* Defining a PHP Function */
  function writeMessage()
  {
  echo "You are really a nice person, Have a nice time!";
  }
  /* Calling a PHP Function */
  writeMessage();
  ?>

You can check presence of GET parameter in URL and call function accordingly:

if(isset($_GET['writeMessage'])){
   writeMessage();
}

Of course it doesnt, especially not in that way. For me, it seems to be a horrible idea to call PHP Functions from the address bar, but if you insist:

append the function name to your url like this:

http://myWebSite.com/myFile.php?func=writeMessage

And in the PHP File:

<?php
    $func = filter_var($_GET["func"]);
    call_user_func($func);
?>

Try:

http://myWebSite.com/myFile.php?writeMessage=1

And:

<?php
 /* Defining a PHP Function */
 function writeMessage()
 {
    echo "You are really a nice person, Have a nice time!";
 }
 /* Calling a PHP Function */
 if(isset($_GET['writeMessage']) && $_GET['writeMessage'] == 1){
   writeMessage();
 }
?>

A simple way that i would use given that you dont have too many functions is to use a if statement at the top of the php file and check the parameter of the url.

Lets say url:

http://myWebSite.com/myFile.php?writeMessage

Turn it into:

http://myWebSite.com/myFile.php?function=writeMessage

code:

<?php
  $function = $_GET['function'];
  if($function == "writeMessage") {
    // writeMessage();
  }
?>

You can do something like this:

<?php

function writeMessage() {
    echo "You're a nice person";
}

$writeMessageArg = $_GET['writeMessage']; /* grabs the argument from the URL */

if (isset($writeMessageArg)) {
    writeMessage();
}

?>

For a generic approach

<?php

$q = $_SERVER['QUERY_STRING'];

function TestFunc() {
    echo "TestFunc() called.";
}

$q();

?>

You can call the TestFunc() by entering the following url in the address bar:

http://myWebSite.com/myFile.php?TestFunc