Article Diary - General Knowledge Digest

Geo-location Mapping With Google Maps API & PHP

Using a combination of a couple APIs, PHP and Curl you can easily incorporate Google Maps into your website that fairly accurately identify a visitor's location. Knowing a users location and further being able to map the location has many practical applications. I am going to breakdown the core elements of creating a map just like the one above. I plan on following up soon with more advanced Google Maps examples.
 
You will need the users' address to begin. If you run a site that collects that information during registration it can be used for mapping otherwise you can get the users city, state and country by grabbing their IP address and then calling one of the available geocoding APIs available.
 
Grab the users IP address.
$ip = $_SERVER['REMOTE_ADDR'];
 
Get the users City, State and Country.
$sturl = 'http://api.hostip.info/get_html.php?ip='.$ip;
$ch = curl_init($sturl);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch,CURLOPT_TIMEOUT,10);
$res = curl_exec($ch);
$resinfo = curl_getinfo($ch);
curl_close($ch);
preg_match('/City: ([a-zA-Z].+[a-zA-Z]+)/', $res, $r);
preg_match('/ (([A-Z][A-Z])/', $res, $s);
$city = $r[1];
$country = $s[1];
 
The above API at http://hostip.info can also return the latitude and longitude which is needed to map the location however for the purposes of this demo I am using the Google geo locator API. You will also need a Google Maps API key which can be requested from http://code.google.com/apis/maps/.
 
Call the Google API to get the latitude and longitude.
$key = "Your Google Maps API Key";
$address = urlencode($city.", ".$country);
$sturl = 'http://maps.google.com/maps/geo?q=' . $address . '&output=csv&key=' . $key;
$ch = curl_init($sturl);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
curl_setopt($ch,CURLOPT_TIMEOUT,10);
$res = curl_exec($ch);
$resinfo = curl_getinfo($ch);
curl_close($ch);
$res = explode(",",$res);
$latitude = $res[2];
$longitude = $res[3];
 
Insert an image tag with the following SRC referencing Google's API.
http://maps.google.com/staticmap?key=' . $key . '&size=506x280&markers=' . $latitude . ',' . $longitude . '&zoom=3
 
This is just the tip of the iceberg. For more details on the API visit the Google documentation at http://code.google.com/apis/maps/documentation/.
 
Click here to download the PHP source code.
 
4 (1)
Article Rating (1 Votes)
Rate this article
Attached Files
There are no attachments for this article.
Comments
There are no comments for this article. Be the first to post a comment.
Name
Email
Security Code Security Code
Related Articles RSS Feed
ValidForm Builder - Creating Forms With Validation
Viewed 1138 times since Wed, Apr 21, 2010
Web Application Security Tools & Scanner Applications
Viewed 1546 times since Mon, Mar 22, 2010
dTree - Flexible JavaScript Tree Menu
Viewed 1781 times since Thu, Jan 14, 2010
Create Navigation Menu Easily with jQuery Menu
Viewed 1319 times since Thu, Dec 31, 2009
File Upload in PHP - PHP File Upload Script
Viewed 2586 times since Thu, Nov 5, 2009
mbSlider - Highly Customizable Content Slider
Viewed 1177 times since Mon, Jul 26, 2010
Search Engine Optimization: Tags of Importance for SEO
Viewed 1149 times since Tue, Oct 12, 2010
Lorem Ipsum Dolor Sit Amet
Viewed 1658 times since Tue, Oct 6, 2009
Free Android GUI PSD File
Viewed 1509 times since Fri, Dec 4, 2009