*a constant parallactic paradox, sublime*

Posts tagged “PHP

Dates in PHP (Tomorrow, Yesterday, Today of a Given Date)

<?php
echo “<h4>Date Yesterday</h4>”;
$yesterday = date(“Y-m-d”, time()-86400);
echo $yesterday;

echo “<h4>Date Today</h4>”;
echo date(“Y-m-d”);

echo “<h4>Date Tomorrow</h4>”;
$tomorrow = date(“Y-m-d”, time()+86400);
echo $tomorrow;

echo “<hr>”;
echo “<h4>Previous Date from User-defined Date</h4>”;

$gdate = “2008-07-11”;
echo “(” . $gdate . ” supplied.) <br>”;
$dt = strtotime($gdate);
echo date(“Y-m-d”, $dt-86400);

echo “<h4>Next Date from User-defined Date</h4>”;
echo “(” . $gdate . ” supplied.) <br>”;
$dt = strtotime($gdate);
echo date(“Y-m-d”, $dt+86400);

// DAYS IN BETWEEN TWO DATES

function days_in_between($s, $e){
$d = array();
$s = strtotime($s);
$e = strtotime($e);
for($n=$s; $n<=$e; $n=$n+86400){
array_push($d, strftime(“%Y-%m-%d”, $n));
}
return $d;

}

?>


Useful PHP Functions

These are three of my favorite PHP functions. 😀

string file_get_contents ( string $filename [, int $flags [, resource $context [, int $offset [, int $maxlen ]]]] )Get the contents of a url.

Example:

// following code will display the contents of the web page http://www.example.com
$url = “http://www.example.com&#8221;;
$contents = file_get_contents($url);
echo $contents;

bool mail ( string $to , string $subject , string $message [, string $additional_headers [, string $additional_parameters ]] )Requires an email server. This functions programatically sends an email based on the given parameters.
Example:

// send an email to someone@somedomain.com
$to=”someone@somedomain.com
$subj = “example”;
$message=”this is an email”;
if(mail($to, $subj, $message)) echo “Email was sent”;
else echo “Email sending failed.”;

int fwrite ( resource $handle , string $string [, int $length ] ) Write something to a file. Note that the file and it’s parent directory should have permissions granted to a user such as “apache” or “www-data”.

Example:

// open a file called test.txt and if it does not exist, attempt to create it; place the pointer at the begining of the file
$handle = fopen(“test.txt”, “a+”);
$data = “I am programatically written.\n”;
fwrite($handle, $data);
fclose($handle);

I’ll stick with these 3 functions for the meantime. With this though, you can make programs such as:

  • A simple email interface. 😀
  • A logging system using just the last function
  • A proxy browser or something.

PHP SESSION

This post was originally titled "PHP Developer Essentials" which was what I really wanted to post instead of "PHP Essentials". But as I was at it, I got really bored and I realize, I really just wanted to list all my favorite or let me just say "mostly used" php functions.

But to preserve the efforts, let me just leave what I have already typed here—Creating a session with PHP.

Creating a Session

login.php

<?php
$login_name = $_POST[‘username’];
$login_password = $_POST[‘password’];
if($login_name==’admin’ && $login_password==’@dm!n’){
   session_start();
   session_cache_expire(15);
   $_SESSION[‘user’] = $_POST[‘username’];
   header("Location: ‘home.html’");
}
else{
   die("Authentication Failed");
}
?>

What this simple program does, is get post data from a form that uses the POST method and defined the URL of this code as the form target. The form will look like:

<form action=’login.php’ method=’post’>
Username: <input type=’text’ name=’username’>
Password: <input type=’password’ name=’password’>
<input type=’submit’ value=’Login’>

After retrieving post data, it will validate the user inputs then start a session and store the login data (username) in a session variable called (user). It will then set the window location to the home page using the header() function.