PHP Calendar Functions

PHP Calendar Introduction

The calendar functions are useful when working with different calendar formats. The standard it is based on is the Julian day count (Julian day count is a count of days starting from January 1, 4713 B.C.). Note that the Julian day count is not the same as the Julian calendar!
Note: To convert between calendar formats, you must first convert to Julian day count, then to the calendar format.

---

Installation

The windows version of PHP has built-in support for the calendar extension. So, the calendar functions will work automatically.
However, if you are running the Linux version of PHP, you will have to compile PHP with --enable-calendar to get the calendar functions to work.

---

PHP Calendar Functions

PHP: indicates the earliest version of PHP that supports the function.

Function	Description	PHP
cal_days_in_month()	Returns the number of days in a month for a specified year and calendar	4
cal_from_jd()	Converts a Julian day count into a date of a specified calendar	4
cal_info()	Returns information about a given calendar	4
cal_to_jd()	Converts a date to Julian day count	4
easter_date()	Returns the Unix timestamp for midnight on Easter of a specified year	3
easter_days()	Returns the number of days after March 21, on which Easter falls for a specified year	3
FrenchToJD()	Converts a French Republican date to a Julian day count	3
GregorianToJD()	Converts a Gregorian date to a Julian day count	3
JDDayOfWeek()	Returns the day of a week	3
JDMonthName()	Returns a month name	3
JDToFrench()	Converts a Julian day count to a French Republican date	3
JDToGregorian()	Converts a Julian day count to a Gregorian date	3
jdtojewish()	Converts a Julian day count to a Jewish date	3
JDToJulian()	Converts a Julian day count to a Julian date	3
jdtounix()	Converts a Julian day count to a Unix timestamp	4
JewishToJD()	Converts a Jewish date to a Julian day count	3
JulianToJD()	Converts a Julian date to a Julian day count	3
unixtojd()	Converts a Unix timestamp to a Julian day count	4

---

PHP Calendar Constants

PHP: indicates the earliest version of PHP that supports the constant.

Constant	Description	PHP
CAL_GREGORIAN	Gregorian calendar	3
CAL_JULIAN	Julian calendar	3
CAL_JEWISH	Jewish calendar	3
CAL_FRENCH	French Republican calendar	3
CAL_NUM_CALS		3
CAL_DOW_DAYNO		3
CAL_DOW_SHORT		3
CAL_DOW_LONG		3
CAL_MONTH_GREGORIAN_SHORT		3
CAL_MONTH_GREGORIAN_LONG		3
CAL_MONTH_JULIAN_SHORT		3
CAL_MONTH_JULIAN_LONG		3
CAL_MONTH_JEWISH		3
CAL_MONTH_FRENCH		3
CAL_EASTER_DEFAULT		4
CAL_EASTER_ROMAN		4
CAL_EASTER_ALWAYS_GREGORIAN		4
CAL_EASTER_ALWAYS_JULIAN		4
CAL_JEWISH_ADD_ALAFIM_GERESH		5
CAL_JEWISH_ADD_ALAFIM		5
CAL_JEWISH_ADD_GERESHAYIM		5

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PHP Array Functions

PHP Array Introduction
The array functions allow you to manipulate arrays.
PHP supports both simple and multi-dimensional arrays. There are also specific functions for populating arrays from database queries.

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Installation

The array functions are part of the PHP core. There is no installation needed to use these functions.

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PHP Array Functions

PHP: indicates the earliest version of PHP that supports the function.

Function	Description	PHP
array()	Creates an array	3
array_change_key_case()	Returns an array with all keys in lowercase or uppercase	4
array_chunk()	Splits an array into chunks of arrays	4
array_combine()	Creates an array by using one array for keys and another for its values	5
array_count_values()	Returns an array with the number of occurrences for each value	4
array_diff()	Compares array values, and returns the differences	4
array_diff_assoc()	Compares array keys and values, and returns the differences	4
array_diff_key()	Compares array keys, and returns the differences	5
array_diff_uassoc()	Compares array keys and values, with an additional user-made function check, and returns the differences	5
array_diff_ukey()	Compares array keys, with an additional user-made function check, and returns the differences	5
array_fill()	Fills an array with values	4
array_filter()	Filters elements of an array using a user-made function	4
array_flip()	Exchanges all keys with their associated values in an array	4
array_intersect()	Compares array values, and returns the matches	4
array_intersect_assoc()	Compares array keys and values, and returns the matches	4
array_intersect_key()	Compares array keys, and returns the matches	5
array_intersect_uassoc()	Compares array keys and values, with an additional user-made function check, and returns the matches	5
array_intersect_ukey()	Compares array keys, with an additional user-made function check, and returns the matches	5
array_key_exists()	Checks if the specified key exists in the array	4
array_keys()	Returns all the keys of an array	4
array_map()	Sends each value of an array to a user-made function, which returns new values	4
array_merge()	Merges one or more arrays into one array	4
array_merge_recursive()	Merges one or more arrays into one array	4
array_multisort()	Sorts multiple or multi-dimensional arrays	4
array_pad()	Inserts a specified number of items, with a specified value, to an array	4
array_pop()	Deletes the last element of an array	4
array_product()	Calculates the product of the values in an array	5
array_push()	Inserts one or more elements to the end of an array	4
array_rand()	Returns one or more random keys from an array	4
array_reduce()	Returns an array as a string, using a user-defined function	4
array_reverse()	Returns an array in the reverse order	4
array_search()	Searches an array for a given value and returns the key	4
array_shift()	Removes the first element from an array, and returns the value of the removed element	4
array_slice()	Returns selected parts of an array	4
array_splice()	Removes and replaces specified elements of an array	4
array_sum()	Returns the sum of the values in an array	4
array_udiff()	Compares array values in a user-made function and returns an array	5
array_udiff_assoc()	Compares array keys, and compares array values in a user-made function, and returns an array	5
array_udiff_uassoc()	Compares array keys and array values in user-made functions, and returns an array	5
array_uintersect()	Compares array values in a user-made function and returns an array	5
array_uintersect_assoc()	Compares array keys, and compares array values in a user-made function, and returns an array	5
array_uintersect_uassoc()	Compares array keys and array values in user-made functions, and returns an array	5
array_unique()	Removes duplicate values from an array	4
array_unshift()	Adds one or more elements to the beginning of an array	4
array_values()	Returns all the values of an array	4
array_walk()	Applies a user function to every member of an array	3
array_walk_recursive()	Applies a user function recursively to every member of an array	5
arsort()	Sorts an array in reverse order and maintain index association	3
asort()	Sorts an array and maintain index association	3
compact()	Create array containing variables and their values	4
count()	Counts elements in an array, or properties in an object	3
current()	Returns the current element in an array	3
each()	Returns the current key and value pair from an array	3
end()	Sets the internal pointer of an array to its last element	3
extract()	Imports variables into the current symbol table from an array	3
in_array()	Checks if a specified value exists in an array	4
key()	Fetches a key from an array	3
krsort()	Sorts an array by key in reverse order	3
ksort()	Sorts an array by key	3
list()	Assigns variables as if they were an array	3
natcasesort()	Sorts an array using a case insensitive "natural order" algorithm	4
natsort()	Sorts an array using a "natural order" algorithm	4
next()	Advance the internal array pointer of an array	3
pos()	Alias of current()	3
prev()	Rewinds the internal array pointer	3
range()	Creates an array containing a range of elements	3
reset()	Sets the internal pointer of an array to its first element	3
rsort()	Sorts an array in reverse order	3
shuffle()	Shuffles an array	3
sizeof()	Alias of count()	3
sort()	Sorts an array	3
uasort()	Sorts an array with a user-defined function and maintain index association	3
uksort()	Sorts an array by keys using a user-defined function	3
usort()	Sorts an array by values using a user-defined function	3

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PHP Array Constants

PHP: indicates the earliest version of PHP that supports the constant.

Constant	Description	PHP
CASE_LOWER	Used with array_change_key_case() to convert array keys to lower case
CASE_UPPER	Used with array_change_key_case() to convert array keys to upper case
SORT_ASC	Used with array_multisort() to sort in ascending order
SORT_DESC	Used with array_multisort() to sort in descending order
SORT_REGULAR	Used to compare items normally
SORT_NUMERIC	Used to compare items numerically
SORT_STRING	Used to compare items as strings
SORT_LOCALE_STRING	Used to compare items as strings, based on the current locale	4
COUNT_NORMAL
COUNT_RECURSIVE
EXTR_OVERWRITE
EXTR_SKIP
EXTR_PREFIX_SAME
EXTR_PREFIX_ALL
EXTR_PREFIX_INVALID
EXTR_PREFIX_IF_EXISTS
EXTR_IF_EXISTS
EXTR_REFS

 http://www.w3schools.com/php/php_ref_array.asp

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PHP Example - AJAX Poll

AJAX Poll

The following example will demonstrate a poll where the result is shown without reloading.

Do you like PHP and AJAX so far?

Yes:
No:

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Example Explained - The HTML Page

When a user choose an option above, a function called "getVote()" is executed. The function is triggered by the "onclick" event:

<html>
<head>
<script type="text/javascript">
function getVote(int)
{
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("poll").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","poll_vote.php?vote="+int,true);
xmlhttp.send();
}
</script>
</head>
<body>

<div id="poll">
<h3>Do you like PHP and AJAX so far?</h3>
<form>
Yes:
<input type="radio" name="vote" value="0" onclick="getVote(this.value)" />
<br />No:
<input type="radio" name="vote" value="1" onclick="getVote(this.value)" />
</form>
</div>

</body>
</html>

The getVote() function does the following:

• Create an XMLHttpRequest object
• Create the function to be executed when the server response is ready
• Send the request off to a file on the server
• Notice that a parameter (vote) is added to the URL (with the value of the yes or no option)

---

The PHP File

The page on the server called by the JavaScript above is a PHP file called "poll_vote.php":

<?php
$vote = $_REQUEST['vote'];

//get content of textfile
$filename = "poll_result.txt";
$content = file($filename);

//put content in array
$array = explode("||", $content[0]);
$yes = $array[0];
$no = $array[1];

if ($vote == 0)
  {
  $yes = $yes + 1;
  }
if ($vote == 1)
  {
  $no = $no + 1;
  }

//insert votes to txt file
$insertvote = $yes."||".$no;
$fp = fopen($filename,"w");
fputs($fp,$insertvote);
fclose($fp);
?>

<h2>Result:</h2>
<table>
<tr>
<td>Yes:</td>
<td>
<img src="poll.gif"
width='<?php echo(100*round($yes/($no+$yes),2)); ?>'
height='20'>
<?php echo(100*round($yes/($no+$yes),2)); ?>%
</td>
</tr>
<tr>
<td>No:</td>
<td>
<img src="poll.gif"
width='<?php echo(100*round($no/($no+$yes),2)); ?>'
height='20'>
<?php echo(100*round($no/($no+$yes),2)); ?>%
</td>
</tr>
</table>

The value is sent from the JavaScript, and the following happens:

1. Get the content of the "poll_result.txt" file
2. Put the content of the file in variables and add one to the selected variable
3. Write the result to the "poll_result.txt" file
4. Output a graphical representation of the poll result

---

The Text File

The text file (poll_result.txt) is where we store the data from the poll.
It is stored like this:

0||0

The first number represents the "Yes" votes, the second number represents the "No" votes.
Note: Remember to allow your web server to edit the text file. Do NOT give everyone access, just the web server (PHP).

http://www.w3schools.com/php/php_ajax_poll.asp

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PHP Example - AJAX RSS Reader

An RSS Reader is used to read RSS Feeds.

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AJAX RSS Reader

The following example will demonstrate an RSS reader, where the RSS-feed is loaded into a webpage without reloading:

Select an RSS-feed: Google News MSNBC News

RSS-feed will be listed here...

---

Example Explained - The HTML Page

When a user selects an RSS-feed in the dropdown list above, a function called "showResult()" is executed. The function is triggered by the "onchange" event:

<html>
<head>
<script type="text/javascript">
function showRSS(str)
{
if (str.length==0)
  {
  document.getElementById("rssOutput").innerHTML="";
  return;
  }
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("rssOutput").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","getrss.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>

<form>
<select onchange="showRSS(this.value)">
<option value="">Select an RSS-feed:</option>
<option value="Google">Google News</option>
<option value="MSNBC">MSNBC News</option>
</select>
</form>
<br />
<div id="rssOutput">RSS-feed will be listed here...</div>
</body>
</html>

The showResult() function does the following:

• Check if an RSS-feed is selected
• Create an XMLHttpRequest object
• Create the function to be executed when the server response is ready
• Send the request off to a file on the server
• Notice that a parameter (q) is added to the URL (with the content of the dropdown list)

---

The PHP File

The page on the server called by the JavaScript above is a PHP file called "getrss.php":

<?php
//get the q parameter from URL
$q=$_GET["q"];

//find out which feed was selected
if($q=="Google")
  {
  $xml=("http://news.google.com/news?ned=us&topic=h&output=rss");
  }
elseif($q=="MSNBC")
  {
  $xml=("http://rss.msnbc.msn.com/id/3032091/device/rss/rss.xml");
  }

$xmlDoc = new DOMDocument();
$xmlDoc->load($xml);

//get elements from "<channel>"
$channel=$xmlDoc->getElementsByTagName('channel')->item(0);
$channel_title = $channel->getElementsByTagName('title')
->item(0)->childNodes->item(0)->nodeValue;
$channel_link = $channel->getElementsByTagName('link')
->item(0)->childNodes->item(0)->nodeValue;
$channel_desc = $channel->getElementsByTagName('description')
->item(0)->childNodes->item(0)->nodeValue;

//output elements from "<channel>"
echo("<p><a href='" . $channel_link
  . "'>" . $channel_title . "</a>");
echo("<br />");
echo($channel_desc . "</p>");

//get and output "<item>" elements
$x=$xmlDoc->getElementsByTagName('item');
for ($i=0; $i<=2; $i++)
  {
  $item_title=$x->item($i)->getElementsByTagName('title')
  ->item(0)->childNodes->item(0)->nodeValue;
  $item_link=$x->item($i)->getElementsByTagName('link')
  ->item(0)->childNodes->item(0)->nodeValue;
  $item_desc=$x->item($i)->getElementsByTagName('description')
  ->item(0)->childNodes->item(0)->nodeValue;

  echo ("<p><a href='" . $item_link
  . "'>" . $item_title . "</a>");
  echo ("<br />");
  echo ($item_desc . "</p>");
  }
?>

When an RSS-feed is sent from the JavaScript, the following happens:

• Check which feed was selected
• Create a new XML DOM object
• Load the RSS document in the xml variable
• Extract and output elements from the channel element
• Extract and output elements from the item element

http://www.w3schools.com/php/php_ajax_rss_reader.asp

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PHP Example - AJAX Live Search

AJAX can be used to create more user-friendly and interactive searches.

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AJAX Live Search

The following example will demonstrate a live search, where you get search results while you type.
Live search has many benefits compared to traditional searching:

• Results are shown as you type
• Results narrow as you continue typing
• If results become too narrow, remove characters to see a broader result

Search for a W3Schools page in the input field below:

The results in the example above are found in an XML file (links.xml). To make this example small and simple, only six results are available.

---

Example Explained - The HTML Page

When a user types a character in the input field above, the function "showResult()" is executed. The function is triggered by the "onkeyup" event:

<html>
<head>
<script type="text/javascript">
function showResult(str)
{
if (str.length==0)
  {
  document.getElementById("livesearch").innerHTML="";
  document.getElementById("livesearch").style.border="0px";
  return;
  }
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("livesearch").innerHTML=xmlhttp.responseText;
    document.getElementById("livesearch").style.border="1px solid #A5ACB2";
    }
  }
xmlhttp.open("GET","livesearch.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>

<form>
<input type="text" size="30" onkeyup="showResult(this.value)" />
<div id="livesearch"></div>
</form>

</body>
</html>

Source code explanation:
If the input field is empty (str.length==0), the function clears the content of the livesearch placeholder and exits the function.
If the input field is not empty, the showResult() function executes the following:

• Create an XMLHttpRequest object
• Create the function to be executed when the server response is ready
• Send the request off to a file on the server
• Notice that a parameter (q) is added to the URL (with the content of the input field)

---

The PHP File

The page on the server called by the JavaScript above is a PHP file called "livesearch.php".
The source code in "livesearch.php" searches an XML file for titles matching the search string and returns the result:

<?php
$xmlDoc=new DOMDocument();
$xmlDoc->load("links.xml");

$x=$xmlDoc->getElementsByTagName('link');

//get the q parameter from URL
$q=$_GET["q"];

//lookup all links from the xml file if length of q>0
if (strlen($q)>0)
{
$hint="";
for($i=0; $i<($x->length); $i++)
  {
  $y=$x->item($i)->getElementsByTagName('title');
  $z=$x->item($i)->getElementsByTagName('url');
  if ($y->item(0)->nodeType==1)
    {
    //find a link matching the search text
    if (stristr($y->item(0)->childNodes->item(0)->nodeValue,$q))
      {
      if ($hint=="")
        {
        $hint="<a href='" .
        $z->item(0)->childNodes->item(0)->nodeValue .
        "' target='_blank'>" .
        $y->item(0)->childNodes->item(0)->nodeValue . "</a>";
        }
      else
        {
        $hint=$hint . "<br /><a href='" .
        $z->item(0)->childNodes->item(0)->nodeValue .
        "' target='_blank'>" .
        $y->item(0)->childNodes->item(0)->nodeValue . "</a>";
        }
      }
    }
  }
}

// Set output to "no suggestion" if no hint were found
// or to the correct values
if ($hint=="")
  {
  $response="no suggestion";
  }
else
  {
  $response=$hint;
  }

//output the response
echo $response;
?>

If there is any text sent from the JavaScript (strlen($q) > 0), the following happens:

• Load an XML file into a new XML DOM object
• Loop through all <title> elements to find matches from the text sent from the JavaScript
• Sets the correct url and title in the "$response" variable. If more than one match is found, all matches are added to the variable
• If no matches are found, the $response variable is set to "no suggestion"

http://www.w3schools.com/php/php_ajax_livesearch.asp

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PHP Example - AJAX and XML

AJAX can be used for interactive communication with an XML file.

---

AJAX XML Example

The following example will demonstrate how a web page can fetch information from an XML file with AJAX:

Example

Select a CD: Bob Dylan Bee Gees Cat Stevens

CD info will be listed here...

---

Example Explained - The HTML Page

When a user selects a CD in the dropdown list above, a function called "showCD()" is executed. The function is triggered by the "onchange" event:

<html>
<head>
<script type="text/javascript">
function showCD(str)
{
if (str=="")
  {
  document.getElementById("txtHint").innerHTML="";
  return;
  }
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","getcd.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>

<form>
Select a CD:
<select name="cds" onchange="showCD(this.value)">
<option value="">Select a CD:</option>
<option value="Bob Dylan">Bob Dylan</option>
<option value="Bonnie Tyler">Bonnie Tyler</option>
<option value="Dolly Parton">Dolly Parton</option>
</select>
</form>
<div id="txtHint"><b>CD info will be listed here...</b></div>

</body>
</html>

The showCD() function does the following:

• Check if a CD is selected
• Create an XMLHttpRequest object
• Create the function to be executed when the server response is ready
• Send the request off to a file on the server
• Notice that a parameter (q) is added to the URL (with the content of the dropdown list)

---

The PHP File

The page on the server called by the JavaScript above is a PHP file called "getcd.php".
The PHP script loads an XML document, "cd_catalog.xml", runs a query against the XML file, and returns the result as HTML:

<?php
$q=$_GET["q"];

$xmlDoc = new DOMDocument();
$xmlDoc->load("cd_catalog.xml");

$x=$xmlDoc->getElementsByTagName('ARTIST');

for ($i=0; $i<=$x->length-1; $i++)
{
//Process only element nodes
if ($x->item($i)->nodeType==1)
  {
  if ($x->item($i)->childNodes->item(0)->nodeValue == $q)
    {
    $y=($x->item($i)->parentNode);
    }
  }
}

$cd=($y->childNodes);

for ($i=0;$i<$cd->length;$i++)
{
//Process only element nodes
if ($cd->item($i)->nodeType==1)
  {
  echo("<b>" . $cd->item($i)->nodeName . ":</b> ");
  echo($cd->item($i)->childNodes->item(0)->nodeValue);
  echo("<br />");
  }
}
?>

When the CD query is sent from the JavaScript to the PHP page, the following happens:

1. PHP creates an XML DOM object
2. Find all <artist> elements that matches the name sent from the JavaScript
3. Output the album information (send to the "txtHint" placeholder)

http://www.w3schools.com/php/php_ajax_xml.asp

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PHP and AJAX

PHP - AJAX and MySQL

AJAX can be used for interactive communication with a database.

---

AJAX Database Example

The following example will demonstrate how a web page can fetch information from a database with AJAX:

Example

Select a person: Peter Griffin Lois Griffin Joseph Swanson Glenn Quagmire

Person info will be listed here...

---

Example Explained - The MySQL Database

The database table we use in the example above looks like this:

id	FirstName	LastName	Age	Hometown	Job
1	Peter	Griffin	41	Quahog	Brewery
2	Lois	Griffin	40	Newport	Piano Teacher
3	Joseph	Swanson	39	Quahog	Police Officer
4	Glenn	Quagmire	41	Quahog	Pilot

---

Example Explained - The HTML Page

When a user selects a user in the dropdown list above, a function called "showUser()" is executed. The function is triggered by the "onchange" event:

<html>
<head>
<script type="text/javascript">
function showUser(str)
{
if (str=="")
  {
  document.getElementById("txtHint").innerHTML="";
  return;
  }
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
    }
  }
xmlhttp.open("GET","getuser.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>

<form>
<select name="users" onchange="showUser(this.value)">
<option value="">Select a person:</option>
<option value="1">Peter Griffin</option>
<option value="2">Lois Griffin</option>
<option value="3">Glenn Quagmire</option>
<option value="4">Joseph Swanson</option>
</select>
</form>
<br />
<div id="txtHint"><b>Person info will be listed here.</b></div>

</body>
</html>

The showUser() function does the following:

• Check if a person is selected
• Create an XMLHttpRequest object
• Create the function to be executed when the server response is ready
• Send the request off to a file on the server
• Notice that a parameter (q) is added to the URL (with the content of the dropdown list)

---

The PHP File

The page on the server called by the JavaScript above is a PHP file called "getuser.php".
The source code in "getuser.php" runs a query against a MySQL database, and returns the result in an HTML table:

<?php
$q=$_GET["q"];

$con = mysql_connect('localhost', 'peter', 'abc123');
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

mysql_select_db("ajax_demo", $con);

$sql="SELECT * FROM user WHERE id = '".$q."'";

$result = mysql_query($sql);

echo "<table border='1'>
<tr>
<th>Firstname</th>
<th>Lastname</th>
<th>Age</th>
<th>Hometown</th>
<th>Job</th>
</tr>";

while($row = mysql_fetch_array($result))
  {
  echo "<tr>";
  echo "<td>" . $row['FirstName'] . "</td>";
  echo "<td>" . $row['LastName'] . "</td>";
  echo "<td>" . $row['Age'] . "</td>";
  echo "<td>" . $row['Hometown'] . "</td>";
  echo "<td>" . $row['Job'] . "</td>";
  echo "</tr>";
  }
echo "</table>";

mysql_close($con);
?>

Explanation: When the query is sent from the JavaScript to the PHP file, the following happens:

1. PHP opens a connection to a MySQL server
2. The correct person is found
3. An HTML table is created, filled with data, and sent back to the "txtHint" placeholder

 

http://www.w3schools.com/php/php_ajax_database.asp

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