Where does the trailing space come from?

http://plungjan.name/SO/load.php

The following code will fail if I do not trim the data.

Why does the PHP return "1 " or "0 " instead of "1" or "0" ?

<?php //load.php
if(isset($_POST["id"])){
  $myid = $_POST['id'];
  if($myid == "1"){
    echo "1";
  }else if($myid == "0"){
    echo "0";
  }
}
else {
?>
<!DOCTYPE html>
<html>
<head>
<title>Post something</title>
<script src="http://code.jquery.com/jquery-1.10.0.min.js"></script>
<script type="text/javascript">
$(function() {
  $('#submit').click( function(){
    $.post('load.php', {"id":$('#id').val()}, function(data){
        window.console&&console.log(data,data=="1");
        var val = $.trim(data);
        if(val == "1"){
            $('#resurl').html('Success');
        }else if (val == "0"){
            $('#resurl').html('Failure');
        }else{
            $('#resurl').html('Unknown:[<span>'+val+'</span>]');
        }
    });
  });
});
</script>
</head>
<body>
<input id="id" />
<div id="resurl"></div>
<input type="button" id="submit" />
</html>
<? } ?> 

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LVL 75
Michel PlungjanIT ExpertAsked:
Who is Participating?
 
Chris StanyonConnect With a Mentor Commented:
@robert_schutt is bang on the money but beat me to posting. When you do an AJAX request the response is whatever the script outputs, and you have a space right at the end of your script (after the closing ?> tag). This also gets sent the to AJAX response.

If you're after checking against a number, then consider using parseInt(data)
0
 
duncanb7Commented:
There is typing error, please re-run again

<?php //load.php
if(isset($_POST["id"])){
  $myid = $_POST['id'];
  if($myid == "1"){
    echo "1";
  }else if($myid == "0"){
    echo "0";
  }
}
else {

}
?>
<!DOCTYPE html>
<html>
<head>
<title>Post something</title>
<script src="http://code.jquery.com/jquery-1.10.0.min.js"></script>
<script type="text/javascript">
$(function() {
  $('#submit').click( function(){
    $.post('load.php', {"id":$('#id').val()}, function(data){
        window.console&&console.log(data,data=="1");
        var val = $.trim(data);
        if(val == "1"){
            $('#resurl').html('Success');
        }else if (val == "0"){
            $('#resurl').html('Failure');
        }else{
            $('#resurl').html('Unknown:[<span>'+val+'</span>]');
        }
    });
  });
});
</script>
</head>
<body>
<input id="id" />
<div id="resurl"></div>
<input type="button" id="submit" />
</html>

Open in new window


window.console&&console.log("=="+data+"==",data=="1");

it show "1" and "0" not "1 " && "0 " if
using window.console&&console.log("=="+data+"==",data=="1");
0
 
Michel PlungjanIT ExpertAuthor Commented:
I do not understand what you mean.
I do not see any typing error.
I log data and the boolean data == "1" which is false since the data returned is "1 " and not "1"
0
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duncanb7Commented:
on line 10 on your first post
0
 
Michel PlungjanIT ExpertAuthor Commented:
I changed to

 window.console&&console.log(">>"+data+"<<",data=="1",data=="1 ");

>>1 << false true

So I do not understand what you mean by line 10?
0
 
Robert SchuttConnect With a Mentor Software EngineerCommented:
I copy/pasted the initially posted code into a file and there is actually a space as last character in the code, AFTER the last "}" of the else.
0
 
Robert SchuttSoftware EngineerCommented:
PS: that could have been an unrelated issue, only in the post, but with that file I saw the problem and when I removed the space there, the problem disappeared.
0
 
Chris StanyonCommented:
Actually, just an update to what I said - the space is after the closing php tag, not the one after the closing if bracket. One of the easiest ways to avoid this is to just leave off the closing PHP tag (but only if it's the end of your document). Finish your page like this:

<input type="button" id="submit" />
</html>
<? }

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0
 
Ray PaseurCommented:
This made sense for me.  Please see:
http://www.laprbass.com/RAY_temp_mplungjan.php

<?php // RAY_temp_mplungjan.php
error_reporting(E_ALL);

if(isset($_POST["id"]))
{   // FILTER / NORMALIZE THE REQUEST DATA
    $myid = trim($_POST['id']);

    // USING THE FILTERED DATA
    if($myid == "1")
    {
        echo "1";
    }
    elseif($myid == "0")
    {
        echo "0";
    }
    else
    {   // UNKNOWN
        echo $myid;
    }
}
else {
?>
<!DOCTYPE html>
<html>
<head>
<title>Post something</title>
<script type="text/javascript" src="http://code.jquery.com/jquery-latest.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
  $('#submit').click( function(){
    id = $("#id").val();
    $.post('RAY_temp_mplungjan.php', {id:id}, function(data){
      var val = $.trim(data);
      if(val == "1"){
        $('#resurl').html('Success');
      }else if (val == "0"){
        $('#resurl').html('Failure');
      }else{
        $('#resurl').html('Unknown:[<span>' + val + '</span>]');
      }
    });
  });
});
</script>
</head>
<body>
<input id="id" />
<div id="resurl"></div>
<input type="button" id="submit" />
</html>
<? } ?>

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HTH, ~Ray
0
 
Ray PaseurCommented:
In this post, line 22 opens a control structure, line 23 stops the PHP interpreter.  Then some HTML is sent to the browser.  PHP needs to know when the control structure ends.  That is line 52.  It starts PHP, provides the end of the control structure and then stops PHP.

If the "short open tag" is not set, you would need the complete <?php instead of just the <? to start the PHP interpreter.

I probably would have written this a little differently, but I was in a hurry and just working from what had been posted with the question.
0
 
Ray PaseurCommented:
0
 
Michel PlungjanIT ExpertAuthor Commented:
Thanks for the participation.

I do not exactly see how the code Ray posted is any different than mine, however I understand now that the spurious space came from

} ?>_ <=== here

and that I could delete it or just do

} /* end of php */

which is what I did. Hence I accept this answer as the solution to my issue

Learned something new.
0
 
duncanb7Commented:
I think ChrisStanyon's answer to this thread is much completed and fast
by taking out php closing tab to solve mplungjan's issue completely
(no need to take care of how many space is left before ?>)


If I am wrong, I am sorry and please ignore my post

Duncan
0
 
Michel PlungjanIT ExpertAuthor Commented:
Robert's solution was first, but Chris' explanation was better.

thanks for pointing that out
0
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