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POEchoing empty array values returns "undefined index" error
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  1. POEchoing empty array values returns "undefined index" error
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    copied!<p>I think this is a relatively simple question to answer. Here is the basic layout of what I want to do.</p> <p>I have an array</p> <pre><code>$polarity_array </code></pre> <p>Values of the array are HTML tags which display an image.</p> <p>But some values of these arrays are empty, because I performed a function which UNSETS any array value equal to "No mod in this slot" (A dropdown box selection in a form when they submit something)</p> <p>I then have a heredoc, echoing my HTML page which contains the values of these arrays like such:</p> <pre><code>{$polarity_array['image_polarity1']} {$polarity_array['image_polarity2']} {$polarity_array['image_polarity3']} {$polarity_array['image_polarity4']} {$polarity_array['image_polarity5']} {$polarity_array['image_polarity6']} {$polarity_array['image_polarity7']} {$polarity_array['image_polarity8']} </code></pre> <p>But since some values AREN'T set (and the unset values depend on what the user submitted initially), I get "undefined index" errors.</p> <p>Is there a better way to do this?</p> <pre><code> &lt;?php include_once 'header.php'; require_once 'login_builds.php'; include_once 'functions.php'; //Connect to server $db_server = mysql_connect($db_hostname, $db_username, $db_password); //Select the database for build-related pages mysql_select_db($db_database) or die("Unable to select database: " . mysql_error()); //Retrieve page variables from GET array for inital querying, decode them $buildname = $_GET['buildname']; $author = $_GET['author']; $pageitem = sanitizeString(urldecode($buildname)); $pageauthor = sanitizeString(urldecode($author)); //Set variables for array query and object image retrieval $query_info = "SELECT * FROM weapons WHERE buildname='$pageitem' AND author='$pageauthor'"; $info_result = mysql_query($query_info); $info_array = mysql_fetch_array($info_result); //Remove entries with no mod, and no polarity /* foreach($info_array as $key =&gt; $string) { if($string == "n" || $string == "No mod in this slot") { unset($info_array[$key]); } } */ $page_id = $info_array['id']; $page_author = $info_array['author']; $page_buildname = $info_array['buildname']; $page_weapon = $info_array['weapon']; $page_mod1 = $info_array['mod1']; $page_mod2 = $info_array['mod2']; $page_mod3 = $info_array['mod3']; $page_mod4 = $info_array['mod4']; $page_mod5 = $info_array['mod5']; $page_mod6 = $info_array['mod6']; $page_mod7 = $info_array['mod7']; $page_mod8 = $info_array['mod8']; $page_polarity1 = $info_array['polarity1']; $page_polarity2 = $info_array['polarity2']; $page_polarity3 = $info_array['polarity3']; $page_polarity4 = $info_array['polarity4']; $page_polarity5 = $info_array['polarity5']; $page_polarity6 = $info_array['polarity6']; $page_polarity7 = $info_array['polarity7']; $page_polarity8 = $info_array['polarity8']; $page_category = $info_array['category']; $page_description = $info_array['description']; $page_date = $info_array['date']; $page_hidden = $info_array['hidden']; //Check if the accessing user is the same as the page creator. If not, check if page is hidden. If page is hidden, redirect to index.php. if($_SESSION['username'] != $page_author) { if($page_hidden == y) { header("Location: index.php"); } } //Retrieve Page Main Image $page_main_image = convertImageMainPageWeapon($page_weapon); //Set up mod and polarity associative arrays $mod_array = array( "image_mod1" =&gt; "$page_mod1", "image_mod2" =&gt; "$page_mod2", "image_mod3" =&gt; "$page_mod3", "image_mod4" =&gt; "$page_mod4", "image_mod5" =&gt; "$page_mod5", "image_mod6" =&gt; "$page_mod6", "image_mod7" =&gt; "$page_mod7", "image_mod8" =&gt; "$page_mod8" ); $polarity_array = array( "image_polarity1" =&gt; "$page_polarity1", "image_polarity2" =&gt; "$page_polarity2", "image_polarity3" =&gt; "$page_polarity3", "image_polarity4" =&gt; "$page_polarity4", "image_polarity5" =&gt; "$page_polarity5", "image_polarity6" =&gt; "$page_polarity6", "image_polarity7" =&gt; "$page_polarity7", "image_polarity8" =&gt; "$page_polarity8" ); foreach($mod_array as $key =&gt; $string) { if($string == "No mod in this slot") { unset($mod_array[$key]); } } foreach($polarity_array as $key =&gt; $string) { if($string == "n") { unset($polarity_array[$key]); } } foreach($mod_array as &amp;$string) { if($string != "") { $string = convertImageMod($string); } } foreach($polarity_array as &amp;$string) { if($string != "") { $string = convertImagePolarity($string); } } echo&lt;&lt;&lt;_END &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt; &lt;head&gt; &lt;meta content="en-us" http-equiv="Content-Language" /&gt; &lt;meta content="text/html; charset=utf-8" http-equiv="Content-Type" /&gt; &lt;title&gt;Weapon Build Creator&lt;/title&gt; &lt;link href="styles/main.css" rel="stylesheet" type="text/css" /&gt; &lt;/head&gt; &lt;body style="background-image: url('images/bg.jpg')"&gt; &lt;div id="form" style="form"&gt; &lt;div class="newsdiv"&gt; &lt;br /&gt; &lt;p class="title"&gt;$page_buildname &lt;br /&gt; (ID: $page_id)&lt;/p&gt; &lt;p class="regular_text"&gt;Author: $page_author&lt;br /&gt; Weapon: $page_weapon&lt;/p&gt; &lt;img class="center_image" src="$page_main_image"&gt;&lt;/img&gt;&lt;br /&gt; &lt;p class="mod_text"&gt; MODS AND POLARITIES&lt;/p&gt; &lt;p class="regular_text"&gt;&lt;/p&gt; &lt;?php for($i=1; $i&lt;=8; $i++) { if(isset($polarity_array['image_polarity' . $i])) { echo $polarity_array['image_polarity' . $i]; } else { echo "This slot is empty."; } } ?&gt; &lt;p class="regular_text"&gt; Description:&lt;/p&gt; &lt;div class="description_text_div"&gt; &amp;nbsp;$page_description&lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;br /&gt; &lt;/div&gt; &lt;p class="regular_text"&gt;*comment section currently disabled for beta testing*&lt;/p&gt; &lt;/div&gt; &lt;form action = "authenticate.php" class="regular_text" method="post"&gt; &lt;div class="auto-style1"&gt; &lt;p class="warning_text"&gt; &lt;br /&gt; &lt;br /&gt;&lt;/p&gt; &lt;/div&gt; &lt;/form&gt; &lt;/div&gt; &lt;/div&gt; &lt;/body&gt; &lt;/html&gt; _END; ?&gt; </code></pre>
 

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