Loading names array from server SQL

[jubalbarca]

I have this AJAX-linked PHP file, which gets a username input by the user, checks if it matches the list it has, then sends back a variable to tell the program what to do next (it only offers the log in option if the name matches).

<?php
// retrieve the user name
$name = $_GET['name'];
// generate output depending on the user name received from client
$userNames = array('JAMES', 'BUBBLES', 'SUDOBAAL');
header('Content-Type: text/javascript');
if (in_array(strtoupper($name), $userNames))
  echo json_encode("1");
else if (trim($name) == '')
   echo json_encode("2");
else
   echo json_encode("3");
?>

My problem is linking tis into an SQL table of my users. I have the following table (it's not actually screwed up, but the SQL monitor program won't go fullscreen)

http://img136.imageshack.us/img136/8688/sqlvp8.jpg

I need to be able to replace the UserNames array in the code with the names loaded from the SQL table (the Array already has both usernames currently in the table I know, but that's for testing purposes as well, and I'm going to write a small script to allow new users to register into the table).

Is this possible, and how can I go about it? I'm only a Javascript specialist really, this is new territory for me...

Many thanks

 

[jpadie]

<?php
// retrieve the user name
$name = $_GET['name'];
// generate output depending on the user name received from client
if (empty($name)){
 $return = 2;
} else {
 //connect to mysql here
 $sql = "Select count(*) from usertable where `name` ='%s'";
 $result = mysql_query(sprintf($sql,  mysql_real_escape_string(trim($_GET['name'])));
 if (!$result){
  $return = 3;
 } else {
   $row = mysql_fetch_array($result);
   if ($row[0] > 0){
     $return = 1;
   } else {
     $return = 3;
   }
 }
}
//output the result now
header('Content-Type: text/javascript');
echo json_encode($return);
exit;
?>

 

[jubalbarca]

Many thanks, now the problems of implementation...

<?php
// retrieve the user name
$name = $_GET['name'];
// generate output depending on the user name received from client
if (empty($name)){
 $return = 2;
} else {
 //connect to mysql here
 $conn = mysql_connect("localhost", "", "");
 mysql_select_db("test", $conn);
 $sql = "SELECT count(*) FROM raiders WHERE name ='%s'";
 $result = mysql_query(sprintf($sql,  mysql_real_escape_string(trim($_GET['name'])));
 if (!$result){
  $return = 3;
 } else {
   $row = mysql_fetch_array($result);
   if ($row[0] > 0){
     $return = 1;
   } else {
     $return = 3;
   }
 }
}
//output the result now
header('Content-Type: text/javascript');
echo json_encode($return);
exit;
?>

The bvesetup gies an internal server error from the Javascript. I have tried several things fiddlng wihthe settings, but no dice.

This is the JS block in question;

/////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////// GETTING PLAYER NAME
/////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////
// make asynchronous HTTP request using the XMLHttpRequest object 
function processnames()
{
  // proceed only if the xmlHttp object isn't busy
  if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0)
  {
    // retrieve the name typed by the user on the form
    playername = encodeURIComponent(document.getElementById("myName").value);
//window.alert(playername);
    name = playername;
    // execute the quickstart.php page from the server
    xmlHttp.open("GET", "adbnames.php?name=" + playername, true);
    // define the method to handle server responses
    xmlHttp.onreadystatechange = handleServerResponsenames;
    // make the server request
    xmlHttp.send(null);
  }
  else
    // if the connection is busy, try again after one second  
    setTimeout('processnames()', 1000);
}

// executed automatically when a message is received from the server
function handleServerResponsenames() 
{
  // move forward only if the transaction has completed
  if (xmlHttp.readyState == 4) 
  {
//  window.alert("reponse!");
    // status of 200 indicates the transaction completed successfully
    if (xmlHttp.status == 200) 
    {
      // extract the XML retrieved from the server
jsonResponse = eval(xmlHttp.responseText);
//window.alert(jsonResponse);
namm = jsonResponse;
//window.alert(namm);
	if (namm == 1){
//	window.alert(namm);
	toggleLayer(commentForm);
	}
	else if (namm == 2){
	setTimeout('processnames()', 1000);
//	window.alert(namm);
	}
	else {
	setTimeout('processnames()', 1000);
//	window.alert(namm);
	}

    } 
    // a HTTP status different than 200 signals an error
    else 
    {
      alert("There was a problem accessing the server: " + xmlHttp.statusText);
    }
  }
}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

I'm getting the bottom error, with Internal Server Error being given as the problem.

Yours gratefully,

Jubal

 

[jpadie]

don't encode the return. just echo it instead.

echo $return;

and note that we're not returning an evaluatable object, just a string/number

this is not a js forum but i would recast your script as follows:

// make asynchronous HTTP request using the XMLHttpRequest object
var xmlHttp;
var debug = true;
function processnames(){
	// proceed only if the xmlHttp object isn't busy
	if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0) {
		// retrieve the name typed by the user on the form
		var playername = encodeURIComponent(document.getElementById("myName").value);
		logger(playername);
		
		// execute the quickstart.php page from the server
		xmlHttp.open("GET", "adbnames.php?name=" + playername, true);
		// define the method to handle server responses
		xmlHttp.onreadystatechange = handleServerResponsenames;
		// make the server request
		xmlHttp.send(null);
	}
	else {
		// if the connection is busy, try again after one second  
		setTimeout('processnames()', 1000);
	}
}
	
	// executed automatically when a message is received from the server
function handleServerResponsenames(){
	// move forward only if the transaction has completed
	if (xmlHttp.readyState == 4) {
		logger("reponse! =" + xmlHttp.responseText);
		// status of 200 indicates the transaction completed successfully
		if (xmlHttp.status == 200) {
			namm = xmlHttp.responseText;
			switch (namm) {
				case 1:
					toggleLayer(commentForm); //[red]query is commentForm a global variable?[/red]
					break;
				case 2:
				case 3:
					setTimeout(processNames, 1000);
					break;	
				default:
					logger(namm);
					
			} //end switch
		} //end if status
	} //end if readystate
}
/**
 * helper function to display error log messages without triggering alerts
 * @param {Object} msg
 */
function logger(msg){
	if (debug) {
		if (console) {
			console.log(msg);
		}
		else {
			var n = document.createElement('div');
			with (n.style) {
				border = 'thin solid red';
				backgroundColor = 'white';
				color = 'black';
			}
			n.innerText = msg;
			document.body.appendChild(n);
		}
	}
}

 

[jubalbarca]

It's still screwing up...

CommentForm is the name of a div tag, the toggle function toggles it to visible.

 

[jpadie]

you cannot address elements like that. you are passing a variable as an argument, not the element id.

as for 'screwing up', that is not a helpful diagnosis. the code i posted should output a bunch of stuff either in the console or at the bottom of the page.

 

[jubalbarca]

The toggle function, when tested with a button, works perfectly though...

I'm just getting an 'error on page' message in the Internet Explorer Status bar and nothing at all is working.

 

[jpadie]

use firefox with firebug installed. that should tell you where the error is.

 

[jubalbarca]

OK, I'll get that. Many thanks, as usual.

 

[jpadie]

can you point us to the page in question too?

 

[jubalbarca]

I'm running Apache/MySQL/PHP on my PC, it's all being done on my home system.