How do I use PHP in Javascript?

bsb87angel

I've been googling quite a bit, and i've noticed that there're a lot of different views on it. Some people say that it is possible to mix and PHP and Javascript together, some say not.

I'm a bit confused. -__-

Anyway, here goes my problem. I'm working with a multi-language site, and that being said, i have a database of content placeholders (the languages available are EN, DE, ES and so on). I'm calling out the value by this:

<? echo showDB($_SESSION['lan'], 'val_f_name');?>

But when the validation runs, it gives me an empty prompt instead of "Please fill in your Email Address".

I replaced "Please fill in your Email Address" with the above php code.

function validate_form_email()
{
       	valid = true;
		var emailID=document.user_form.email_address
		var dt=document.user_form.dateofbirth
	if ((emailID.value==null)||(emailID.value=="")){
		alert ( "Please fill in your Email Address" );
		valid = false;
	}
	else if (echeck(emailID.value)==false){
		emailID.value=""
		valid = false;
	}

**this is just part of the javascript.

Note that Connection to mysql database is working fine.

Piranha

First it is NOT possible to combine PHP and JavaScript. PHP is run on the webserver and JavaScript in the browser, so it is not possible to combine them.

But you can generate JavaScript code in PHP that is later run in the client. It is done the exact same way that you do the HTML. And you can use AJAX to make a call from JavaScript to PHP and then retrieve the result.

Second to the problem that the text is not showing. You use a function showDB that is not a standard PHP function, in other words you wrote it yourself. Without knowing the code for that function it is impossible to say what is wrong.

By the way, use <?php instead of <?. All servers can recognice <?php and it will be supported in the future. Not all servers can understand <? and it might disappear in the future.

MarkR

You can generate Javascript code with PHP, however, this is usually undesirable.

If you want to pull localisation strings out of a server-side data structure, it would be better to have a .js file which defines all your localised strings e.g.

var localised_strings = {
  "hello": "Bonjour",
  "goodbye": "Au revoir"
}; // etc

And put that in a separate .js file.

You can then pull that in with a script element and the browser can cache it nicely. If you want this can be generated server-side in PHP.

Mixing code of JS and PHP is confusing and should not generally be done.

Mark

bsb87angel

Piranha wrote:
First it is NOT possible to combine PHP and JavaScript. PHP is run on the webserver and JavaScript in the browser, so it is not possible to combine them.

But you can generate JavaScript code in PHP that is later run in the client. It is done the exact same way that you do the HTML. And you can use AJAX to make a call from JavaScript to PHP and then retrieve the result.

Second to the problem that the text is not showing. You use a function showDB that is not a standard PHP function, in other words you wrote it yourself. Without knowing the code for that function it is impossible to say what is wrong.

By the way, use <?php instead of <?. All servers can recognice <?php and it will be supported in the future. Not all servers can understand <? and it might disappear in the future.

Thanks for enlightening me about PHP and Javascript.
I will check up about AJAX too then.

Not to worry about the function - yes, i wrote it. And, when i used it in the <body> and </body>, it shows me the text from the database.

Thanks for the heads up on <? . I will use <?php for all my pages.

bsb87angel

MarkR wrote:
You can generate Javascript code with PHP, however, this is usually undesirable.

If you want to pull localisation strings out of a server-side data structure, it would be better to have a .js file which defines all your localised strings e.g.
var localised_strings = {
  "hello": "Bonjour",
  "goodbye": "Au revoir"
}; // etc
And put that in a separate .js file.

You can then pull that in with a script element and the browser can cache it nicely. If you want this can be generated server-side in PHP.

Mixing code of JS and PHP is confusing and should not generally be done.

Mark

Thanks for your valuable input, Mark. I'm not sure about localisation strings (guess i'll have to read up more on that), but i'll take note that it's undesirable to mix codes of JS and PHP.