Question

I’m working with UK address data and also International address data.

I need to geocode the address data for use on a google map. I’m doing this using the HTTP service. Ie/ Constructing a query string and passing it to file_get_contents($THEURL).

I’ve managed to geocode 80% of the address data perfectly, however those addresses in countries like Norway and Sweeden that contain special characters will not return a geocode.The code returned is 602 (cannot find an address).

Looking into the documentation I can see that the string sent to google must be UTF8 encoded.

I’ve tried the following to ensure the string is UTF8 encoded / remove the special characters.

1) Using UTF8 encode on the query string – this often results in malformed characters being displayed on the screen.

2) mb_check_encoding reports the string is correctly encoded.

3) Using a function to substitue special characters for thier europiene eqivilents (in the hope google api will compensate.

Can anyone suggest a reason why my method isn’t working (whether to do with encoding or not?).

Answer 1

You need to systematically go through every encoding aspect in your system and define what encoding it is in. Mb_detect_encoding and guesswork are not a good approach here.

You need to check the encoding of:

• incoming data
  • pages
  • GET parameters
  • database connection
  • database table collations
• the script files you work with

If malformed characters occur, chances are you are using ISO-8859-1 or some other non-UTF-8 encoding somewhere. When everything is clean UTF-8, the request should go through.

A very good article on the basics is The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!).