PHP uitvoeren met JavaScript

<script language="javascript">
	function createRequestObject() {
	
	   var req;
		
	   if(window.XMLHttpRequest){
		  req = new XMLHttpRequest();
	   } else if(window.ActiveXObject) {
		  req = new ActiveXObject("Microsoft.XMLHTTP");
	   } else {
		  req = NULL;
		  alert('Probleem met het aanmaken van hetXMLHttpRequest object');
	   }
		
	   return req;
		
	}
    
	var http = createRequestObject();

	function sendRequest() {
		http.open('get', 'depagina.php');
		http.send(null);		  
	}
</script>
<input type="button" value="Test" onclick="sendRequest()" />

<script language="javascript">
	function createRequestObject() {
 
	   var req;
 
	   if(window.XMLHttpRequest){
		  req = new XMLHttpRequest();
	   } else if(window.ActiveXObject) {
		  req = new ActiveXObject("Microsoft.XMLHTTP");
	   } else {
		  req = NULL;
		  alert('Probleem met het aanmaken van hetXMLHttpRequest object');
	   }
 
	   return req;
 
	}
 
	var http = createRequestObject();
 
	function sendRequest() {
		http.open('get', 'depagina.php');
		http.send(null);		  
	}
</script>
<input type="button" value="Test" onclick="sendRequest()" />

<?php
$fp = fopen("bestand.txt", "a");

$gegevens = "TESTERDETEST";

fwrite($fp, $gegevens);

fclose($fp);
?>

<?php
$fp = fopen("bestand.txt", "a");
 
$gegevens = "TESTERDETEST";
 
fwrite($fp, $gegevens);
 
fclose($fp);
?>