PHP未定义的偏移量

I am making a photo gallery and with every photo I can see how many comments there are on that photo. The code that I have is working like it should except that if there are 0 comments it will give the 'Undefined Offset error: 2'
'Undefined Offset error: 3'
'Undefined Offset error: 4'
'Undefined Offset error: 5'
etc.

This is the code to check how many comments there are: (reacties = comments)

// check how many comments every photo has. 
$reacties; 
$query = "select foto from fotosreacties where boek = '" . $_GET['boek'] . "'"; 
if($result = mysql_query($query)){ 
while ($r = mysql_fetch_array($result)){ 
    while ($foto = current($fotoArray)) { 
           if ($foto==$r["foto"]){ 
               $key = key($fotoArray); 
               } // end if 
           next($fotoArray); 
        } // end while 
    if(!isset($reacties[$key])){ 
        $reacties[$key] = 1; 
        } // end if     
    else { 
        $reacties[$key]++; 
        } // end else     
        reset($fotoArray); 

    } // end while 
} // end if     

And this is the code to show the picture and the number of comments:

for($i=$begin; $i < $eind; $i++){ 


$thumb = str_replace($path2, $thumbPath, $fotoArray[$i]); 

   echo "<td align='center'><a href='" . $_SERVER['PHP_SELF'] . "?page=album&boek=" .     $originalPath . "&fotoID=" . $i . "'><img border='0' src='" . $thumb . "' height='100'><br>"; 
echo "<small>reacties ("; 
if($reacties[$i]==0){ 
    echo "0"; 
    } // end if 
else { 
echo $reacties[$i]; 
    } // end else     
echo ")</small>"; 
echo "</a></td>"; 
    $fotonr++; 
    if($fotonr == ($clm + 1)){ 
    echo "</tr>
<tr>"; 
     $fotonr = 1; 
} // end if 

If anyone knows what I have done wrong and/or knows how to solve this it would be great!

You can embed the counter in your query:

select foto, count(*) AS counter_comments from fotosreacties where boek = '" . $_GET['boek'] . "'. In the result, you can use $r['counter_comments'] and check whether its 0 or more.

About your code:

  • Stop using MySQL-functions in new applications since they will be deprecated soon. Use MySQLi or PDO instead!
  • Never trust user input like $_GET, you at least sanitize it by (for example) mysql_real_escape_string().