Questions tagged [php]
PHP is an open-source, multi-paradigm, dynamically-typed, and interpreted scripting language designed initially for server-side web development. Use this tag for questions about programming in the PHP language.
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How can I prevent SQL injection in PHP?
If user input is inserted without modification into an SQL query, then the application becomes vulnerable to SQL injection, like in the following example:
$unsafe_variable = $_POST['user_input'];
...
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"Notice: Undefined variable", "Notice: Undefined index", "Warning: Undefined array key", and "Notice: Undefined offset" using PHP
I'm running a PHP script and continue to receive errors like:
Notice: Undefined variable: my_variable_name in C:\wamp\www\mypath\index.php on line 10
Notice: Undefined index: my_index C:\wamp\www\...
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answers
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Why shouldn't I use mysql_* functions in PHP?
What are the technical reasons for why one shouldn't use mysql_* functions? (e.g. mysql_query(), mysql_connect() or mysql_real_escape_string())?
Why should I use something else even if they work on ...
- 174k
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votes
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PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
PHP ...
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Reference - What does this error mean in PHP?
What is this?
This is a number of answers about warnings, errors, and notices you might encounter while programming PHP and have no clue how to fix them. This is also a Community Wiki, so everyone is ...
568
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PHP mail function doesn't complete sending of e-mail
<?php
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From: yoursite.com';
$to = '[email protected]';
$subject = 'Customer ...
- 5,723
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answers
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UTF-8 all the way through
I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.
Where ...
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How do you parse and process HTML/XML in PHP?
How can one parse HTML/XML and extract information from it?
572
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What is the difference between client-side and server-side programming?
I have this code:
<script type="text/javascript">
var foo = 'bar';
<?php
file_put_contents('foo.txt', ' + foo + ');
?>
var baz = <?php echo 42; ?>;
...
- 518k
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1
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What to do with mysqli problems? Errors like mysqli_fetch_array(): Argument #1 must be of type mysqli_result and such
In my local/development environment, the MySQLi query is performing OK. However, when I upload it on my web host environment, I get this error:
Fatal error: Call to a member function bind_param() on ...
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SQL injection that gets around mysql_real_escape_string()
Is there an SQL injection possibility even when using mysql_real_escape_string() function?
Consider this sample situation. SQL is constructed in PHP like this:
$login = mysql_real_escape_string(...
- 82.8k
301
votes
2
answers
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How to extract and access data from JSON with PHP?
This is intended to be a general reference question and answer covering many of the never-ending "How do I access data in my JSON?" questions. It is here to handle the broad basics of decoding JSON in ...
- 26.4k
2017
votes
27
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How do I get PHP errors to display?
I have checked my PHP ini file (php.ini) and display_errors is set and also error reporting is E_ALL. I have restarted my Apache webserver.
I have even put these lines at the top of my script, and it ...
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388
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Convert one date format into another in PHP
Is there a simple way to convert one date format into another date format in PHP?
I have this:
$old_date = date('y-m-d-h-i-s'); // works
$middle = strtotime($old_date); // ...
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Reference Guide: What does this symbol mean in PHP? (PHP Syntax)
What is this?
This is a collection of questions that come up now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
This ...