vipsa Posted October 7, 2013 Share Posted October 7, 2013 I am a newbie and I have a few questions please: 1. I am trying to get data from a database and display it in a template. So I have created all the connection things and they work and I have created a while loop to loop through the result set and here is the code <code> while ($row = $result->fetch()) { $jokes[] = $row['joketext']; } include 'jokes.html.php'; </code> But when you go to jokes.html.php then it tells you that the array $jokes is undefined. My questions is this:If I create a php file and I create variables or set variables and I then import a template file "Are the variables then availablle to the template file I import? Here is the code for the template file </code> <!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>List of Jokes</title> </head> <body> <p>Here are all the jokes in the database:</p> <?php foreach ($jokes as $joke): ?> <blockquote> <p><?php echo htmlspecialchars($joke, ENT_QUOTES, 'UTF-8'); ?> </p> </blockquote> <?php endforeach; ?> </body> </html> </code> Any help is appreciated Quote Link to comment Share on other sites More sharing options...
mac_gyver Posted October 7, 2013 Share Posted October 7, 2013 there's nothing technically wrong with the snippets of code you posted, provided they are in the same program scope, the loop is actually fetching the data into the $jokes array, and your code is not clearing the $jokes array between where it is being loaded and where it is being used. is the code you posted your actual code and have you confirmed that $jokes actually contains the expected result from the while(){} loop? Quote Link to comment Share on other sites More sharing options...
vipsa Posted October 7, 2013 Author Share Posted October 7, 2013 (edited) The table contains three rows This is a joke Two men are sitting in a bar The blond parks her car Here is all the php code for the connection script which if ran on it's own works fine. But when I include a template page then the page says variable undefined. So how do I get the template page to use the $jokes array? <code> <?php try { $pdo = new PDO('mysql:host=localhost;dbname=learnphp', 'corne', 'lekker1'); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $pdo->exec('SET NAMES "utf8"'); } catch (PDOException $e) { $error = 'Unable to connect to the database server.'; include 'error.html.php'; exit(); } try { $sql = 'SELECT joketext FROM jokes'; $result = $pdo->query($sql); } catch (PDOException $e) { $error = 'Error fetching jokes: ' . $e->getMessage(); include 'error.html.php'; exit(); } while ($row = $result->fetch()) { $jokes[] = $row['joketext']; } include 'jokes.html.php'; </code> and the page supposed to show the results the code is in my first post. Edited October 7, 2013 by vipsa Quote Link to comment Share on other sites More sharing options...
Ch0cu3r Posted October 7, 2013 Share Posted October 7, 2013 That code is fine. The try/catch statments will catch any errors from PDO/Database and display the error. The while loop will populate the $results array with the jokes if the query executed ok. The only time you'll get the Undefined variable: jokes in path/to/jokes.html.php error is if your query is returning no results, because there is no entries in the jokes table or when you physically access that file, ie http://site.com/jokes.html.php. This is because the $jokes array is defined in the file that was including jokes.html.php. The $jokes array is not remembered. Quote Link to comment Share on other sites More sharing options...
vipsa Posted October 8, 2013 Author Share Posted October 8, 2013 I'm sorry but this does not answer my question because why would someone writing a book have code like this if it does not work and I have seen this before so why would the while loop include a file if the variable is not available to the file that is being included? There are results and if you run the code that is in the database connection script it displays the results fine. It is when you want to display the results on another page jokes.html.php when the problem starts for me Quote Link to comment Share on other sites More sharing options...
mac_gyver Posted October 8, 2013 Share Posted October 8, 2013 (edited) again, there is nothing technically wrong with the code, provided the query is working and the code, especially the file name in the include statement, is the actual code, what is the exact error message you got? you also never confirmed that you actually have checked in your program that the $jokes array contains the expected data. in programming you cannot ASSUME anything when you don't get the expected results, you must actually check what the data is and confirm it, in multiple places, as needed, to pin down where it is working and at what point it is not working. Edited October 8, 2013 by mac_gyver Quote Link to comment Share on other sites More sharing options...
vipsa Posted October 8, 2013 Author Share Posted October 8, 2013 There are 2 files database.php jokes.html.php there is a database learnphp with a tables jokes and WITH RECORDS INSIDE THE TABLE I want to display the records on the jokes.html.php page If I run database.php alone then it works fine and I see the results If I open jokes.html.php then I get variable $jokes undefined and a Warning: Invalid argument supplied for foreach() in C:\wamp\www\learnphp\jokes.html.php on line 12 Here is the code for both files: DATABASE.PHP: <?php try { $pdo = new PDO('mysql:host=localhost;dbname=learnphp', 'corne', 'lekker1'); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $pdo->exec('SET NAMES "utf8"'); } catch (PDOException $e) { $error = 'Unable to connect to the database server.'; include 'error.html.php'; exit(); } try { $sql = 'SELECT joketext FROM jokes'; $result = $pdo->query($sql); } catch (PDOException $e) { $error = 'Error fetching jokes: ' . $e->getMessage(); include 'error.html.php'; exit(); } while ($row = $result->fetch()) { $jokes[] = $row['joketext']; } include 'jokes.html.php'; HERE IS THE CODE FOR JOKES.HTML.PHP: <!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>List of Jokes</title> </head> <body> <p><a href="?addjoke">Add your own joke</a></p> <p>Here are all the jokes in the database:</p> <?php foreach ($jokes as $joke): ?> <blockquote> <p><?php echo htmlspecialchars($joke, ENT_QUOTES, 'UTF-8'); ?> </p> </blockquote> <?php endforeach; ?> </body> </html> Now can someone please tell me what is wrong and what I need to do to fix this. I will be very grateful if I could get a clear answer explaining how this is supposed to work Thank you Quote Link to comment Share on other sites More sharing options...
Solution mac_gyver Posted October 8, 2013 Solution Share Posted October 8, 2013 If I run database.php alone then it works fine and I see the results it works because database.php is including the template file - include 'jokes.html.php'; that's the way it is supposed to work. you are not supposed to browse directly to jokes.html.php. it's not a complete web page. it is only the template file that uses the $jokes array. it is only supposed to be included into the file where the $jokes array is being produced. Quote Link to comment Share on other sites More sharing options...
vipsa Posted October 8, 2013 Author Share Posted October 8, 2013 Thank you now I understand it better! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.