How Best to Deal With Differing Character Sets

[jdc44]

I have a web form that inserts user info into a table and sends an email to the department at our building responsible for the info.

During testing, I've found that when entering special characters from the Latin Character set, the characters get interpreted by PHP to be something else.

Example: Into an address input field, I enter: No.1 Place du Vendôme (a french address) .

Note: ( In case it doesn't display correctly, I'll spell it with an o ), in the name Vendome, the o has a "circumflex" or "carrot" over it. This is an html entity of: ô

When I display this on screen, this o gets changed to two characters: an "a" with a left pointing accent - ( à ), and a "?" question-mark.

I'm sure we've all dealt with special characters that get interpreted incorrectly by databases and or code, so I was wondering...
1. Is there any way to know what character set a user is using on their end?
2. Is there any php function(s) out there that I can use to send text through as a check for different character sets that will keep my code from interpreting it incorrectly?

Thanks for any help.

[drew010]

the characters are all represented by different binary numbers, the reason sometimes you will see a different character like a question mark or an a, would be because either the current font you are using, doesnt support these unicode characters, or the charset the browser is using is not set to support the characters. you can use the meta tag content type to specify the character set of utf-8 (which handles the multilingual characters). a table of unicode characters is at http://www1.tip.nl/~t876506/utf8tbl.html. You can see decimal character 153 is the o circumflex.
But in short if the wrong character encoding or font is used then the character will be displayed incorrectly, usually a ? if the charset doesnt even have a character with that code.