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Geocoding

    Geocoding is the process of converting addresses (like "Pune") into geographic coordinates (like latitude - 18.5193 and longitude - 73.8579), which you can use to place markers or position the map. The Google Maps API provides a geocoder class for geocoding addresses dynamically from user input. Accessing the Geocoding service is asynchronous, since the Google Maps API needs to make a call to an external server. For that reason, you need to pass a callback method to execute upon completion of the request. This callback method processes the result(s). To know more details about the geocoding requests, responses and results visit this link.

    Understanding the geocoding requests, responses and results is very important for proper understanding and execution of any geocoding functionality in Google Maps API v3. Let us have a look at the following example...



    The output of the above code will appear as seen in the results section above. The map is initially centered at India, with no text in the search box. Now you need to put in the address that you wish to geocode in the search box and then click on search. If the entered address is valid, a marker will appear on the map at the appropriate location.

    There is some level of error-handling done in this example using the status codes of the geocoding facility in Google Maps API. The status codes return several values depending upon whether the geocode was successful or not and whether any result was returned. The following image will show one such condition where the geocode was successful but did not return anything as the entered address was invalid.


    Some may find the above example a little complex, but the example is not complex at all, it is just that you need to understand the geocoding requests, responses, results and status codes. If anybody wants me to write in depth about the theory of the geocoding, then I will definitely try and write to explain the stuff in as simple language as possible. Till then...Keep mapping!
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  1. GaryApril 1, 2011 at 10:29 AM

    Shreerang Patwardhan,
    Pardon me for asking but is your first name Shreerang or is it Patwardhan. Reason I ask is because when I was in college some of my foreign student friends addressed themselves with the Last name first and First name last. I would like to know out of respect to addressing you.
    My email is to let you know I enjoy your sharing of your skills in computer data building language with all of your followers on-line this is quite generous of you doing so. My real question is to ask you well... how do I start in this process of creating this task of data language inputting? Do I simply open a word document or a spreadsheet to input the info in? I am kind of a novice as you can tell by now. I thought I read some wheres you saying to open a browser... not sure which or what browser, if that is what you might have said at one time to do in order to do the language build. Can you help me through this process, by perhaps sending me a set of instructions to follow to get started? I would surely appreciate it a whole heck of allot. These little gifts of yours to the general viewer of creating a data language input then into an actual visual representation that one can use and work in is quite fascinating to see happen and to know just what it is that “you” as an industry career if only in part.
    So I ask you if I may can you help me with this journey in my learning something new?
    Thanks so much for your time and effort
    Best Regards,
    Gary Bertolo

    ReplyDelete
  2. Shreerang PatwardhanApril 4, 2011 at 2:29 AM

    Hi Gary...My first name is Shreerang...:)Happy to hear that you enjoy my blog. I also enjoy sharing my knowledge with the tech community and would be more than happy to help you out...
    First of all you need to start from the basics if you need to learn something like Google Maps API. If you just enjoy browsing the maps and don't really wish to code then all you need to do is copy the code in the posts and paste it in a normal text file. You can use notepad, wordpad, MS Word if you use windows and gedit, notepad, Open Office Word if you use Linux for the same purpose. Once you have copied the code in one of these files you need to save these files with ".html" extension and not with ".txt" or ".doc" extensions which would be the default ones. Once you get around this, you can double-click on this file and it would open up in your default web-browser.
    Now, the thing is that the code into consideration is javascript. Each browser renders javascript differently. So a map that appears perfect in Firefox, might not work in Google Chrome or IE...Firefox is the best...
    Hope this helps you get started...And if wish to learn google maps API...then you can start reading my blog from the very first post...
    Hope you enjoy my blog...Any suggestions are welcome...
    Thanx for your appreciation.

    ReplyDelete

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