Forms and PHP

[Hugh Janus]

Hello, I have a huge list of selectives in a database. What I want to do is
have 3 lists <selectfuncti on in a form. 1 list will have countrys, another
list will have citys.

When a country is selected, I want the list of citys to show that is in that
country, if there is no citys i want it to go straight to the 3rd list. Is
this possible in php? if so do you have any examples.

Please ask if a part didnt make sense.

Thanks
BW

[Chenky]

Re: Forms and PHP

Hi Hugh,

My simple answer is no. What you want for this is dynamic script ie
JavaScript which is relatively simple to do. PHP is server-side and
doesn't interact with the user unlike JavaScript.

Now my guess is to use an array for all the cities in one country when
u select the country and then write that array into the innerHTML of
the select tag. I'm not too qualified in JavaScript but I dabble and
that would be my method. I'm sure someone else would be able ot provide
a simpler solution though...


Regards,
Josh

[Chenky]

Re: Forms and PHP

Sorry, on second thought you should be able to utilise the database
cache of cities (if that's what you mean) but I have never connected to
a database using javascript and I am unsure if that is possible.

If not, you'll have to cnnect to the database using PHP (if u don't
know how I can show you) and print the data into an array or variable
of some kind. Then continue with my previous suggestion.


Regards,
Josh

[Chenky]

Re: Forms and PHP

Hi Hugh,

My simple answer is no. What you want for this is dynamic script ie
JavaScript which is relatively simple to do. PHP is server-side and
doesn't interact with the user unlike JavaScript.

Now my guess is to use an array for all the cities in one country when
u select the country and then write that array into the innerHTML of
the select tag. I'm not too qualified in JavaScript but I dabble and
that would be my method. I'm sure someone else would be able ot provide
a simpler solution though...


Regards,
Josh

[Colin Fine]

Re: Forms and PHP

Chenky wrote:

Sorry, on second thought you should be able to utilise the database
cache of cities (if that's what you mean) but I have never connected to
a database using javascript and I am unsure if that is possible.
>
If not, you'll have to cnnect to the database using PHP (if u don't
know how I can show you) and print the data into an array or variable
of some kind. Then continue with my previous suggestion.
>
>
Regards,
Josh
>

Not unless you use AJAX. Javascript is running on the user's machine,
and knows nothing of the database.

Colin

[Hugh Janus]

Re: Forms and PHP


"Colin Fine" <news@kindness. demon.co.ukwrot e in message
news:egam40$lfp $3$8302bc10@new s.demon.co.uk.. .

Chenky wrote:

>Sorry, on second thought you should be able to utilise the database
>cache of cities (if that's what you mean) but I have never connected to
>a database using javascript and I am unsure if that is possible.
>>
>If not, you'll have to cnnect to the database using PHP (if u don't
>know how I can show you) and print the data into an array or variable
>of some kind. Then continue with my previous suggestion.
>>
>>
>Regards,
>Josh
>>

>
Not unless you use AJAX. Javascript is running on the user's machine, and
knows nothing of the database.
>
Colin

Hey, do you have any examples I can look at for AJAX and PHP in a dropdown
list?

Thanks
BW

[Chenky]

Re: Forms and PHP

I haven't used AJAX (or heard of it) so Colin's probably more
knowledgeable at that one.

Assuming you're using MySQL, a simple way to achieve what you need is
something like this...


<select name="selectedc ity">
<?
// Next line is name of database
$db = "mydatabase ";

// In next line replace localhost with IP address of database server,
but alot of them are just localhost, and replace username and password
with the obvious

$link = @mysql_connect( "localhost" , "username", "password") ;

if (! $link) {
die("Error: Couldn't connect to MySQL Database");
}
mysql_select_db ($db) or die("Error: Couldn't open MySQL Database");
// Replace name with the column heading containing the city name
$query = mysql_query("SE LECT * FROM cities where name!="");

while ($city = mysql_fetch_arr ay($query)) {
echo "<option value=" . $city['name'] . ">" . $city['name'];
}
?>
</select>

This will print a new...row or thing lol in the drop down list for
every city listed in the database. Any other help just ask ;)

Josh

[universalbitmapper]

Re: Forms and PHP


Hugh Janus wrote:

"Colin Fine" <news@kindness. demon.co.ukwrot e in message
news:egam40$lfp $3$8302bc10@new s.demon.co.uk.. .

Chenky wrote:

Sorry, on second thought you should be able to utilise the database
cache of cities (if that's what you mean) but I have never connected to
a database using javascript and I am unsure if that is possible.
>
If not, you'll have to cnnect to the database using PHP (if u don't
know how I can show you) and print the data into an array or variable
of some kind. Then continue with my previous suggestion.
>
>
Regards,
Josh
>

Not unless you use AJAX. Javascript is running on the user's machine, and
knows nothing of the database.

Colin

>
Hey, do you have any examples I can look at for AJAX and PHP in a dropdown
list?
>
Thanks
BW

There is this kind of hierarchy in web programming:

XHTML->php/mysql -javascript->DOM->XMLHttpReque st

What you want to do is keep the user on the same page even if he has to
use the third drop list. That means you have to keep the data available
to javascript/DOM/XMLHttpRequest.
AJAX is just a buzzword that encompasses dynamically refreshing pages
techniques.
Google search with these keywords + howto, and get going! :-)

[Manuel Lemos]

Re: Forms and PHP

Hello,

on 10/07/2006 10:37 PM Hugh Janus said the following:

Hello, I have a huge list of selectives in a database. What I want to do is
have 3 lists <selectfuncti on in a form. 1 list will have countrys, another
list will have citys.
>
When a country is selected, I want the list of citys to show that is in that
country, if there is no citys i want it to go straight to the 3rd list. Is
this possible in php? if so do you have any examples.

What you want can be done using this forms generation class. It comes
with a linked select custom input that can switch the options of select
input when another input changes.

It can switch options from static arrays or retrieve dynamically from a
database using AJAX:

http://www.phpclasses.org/formsgeneration

Here is a working example of the static version:

http://www.phpclasses.org/browse/file/9879.html

--

Regards,
Manuel Lemos

Metastorage - Data object relational mapping layer generator

http://www.metastorage.net/

PHP Classes - Free ready to use OOP components written in PHP
http://www.phpclasses.org/