Simple preg_replace

[mrdhood]

I know this should be simple but I am terrible with preg_replace and keep returning blank results.

I'm attempting to make "{table}" change to the value of $tables['table'], for example: "SELECT * FROM `{settings}`" would change to "SELECT * FROM `" . $tables['settings'] ."`

[ragax]

I tested this code, it works.

 

$subject='"SELECT * FROM `{settings}`"';
$s=preg_replace('/"SELECT \* FROM `\{([^}]+)\}`"/', '"SELECT * FROM `".$tables[\'\1\']"', $subject);
echo $s;

 

[mrdhood]

I was trying to use $1 :/. I had almost the same thing at one point.

 

How would I go about just changing {table} to $tables[\1\]? That way the following examples wouldn't be bothered:

SELECT `id` FROM `{table}`

SELECT * FROM `{table}` WHERE `id`='1'

and so on.

[mrdhood]

I imagined it'd be something like:

$query = preg_replace('`\{([^}]+)\}`', "self::$config['tables'][$1]", $query);

 

but that errors as

Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING in

 

and

 

$query = preg_replace('`\{([^}]+)\}`', '"self::$config[\'tables\'][$1]'", $query);

as

Parse error: syntax error, unexpected '"' in

[ragax]

How would I go about just changing {table} to $tables[\1\]

 

If that's literally what you want, no problem, but are you sure you literally want $tables[\1] ???

What does the \1 refer to? (How is it going to work in your SELECT statement?)

 

Anyhow:

$subject='"SELECT * FROM `{table}`"';

$s=preg_replace('/"SELECT \* FROM `\{table}`"/', '"SELECT * FROM `".$tables[\\\\1]"', $subject);

 

 

[mrdhood]

$tables = array(
'settings' => $prefix . 'settings',
'users' => $prefix . 'users'
);

$query = "SELECT * FROM `{users}` WHERE `user_id`='" . $Visitor->user_id . "'";
// Should be $query = "SELECT * FROM `" . $tables['users'] . "` WHERE `user_id`='" . $Visitor->user_id . "'";

[ragax]

How is this different from the first solution I gave you?

 

As requested, among other things, it replaces whatever is in the braces: {settings}, {users} or whatever with

$tables['settings'], $tables['users'] or whatever.

 

Please be as clear as possible as it is very hard to troubleshoot regex without extremely clear communication about desired input and output.

[mrdhood]

How is this different from the first solution I gave you?

 

As requested, among other things, it replaces whatever is in the braces: {settings}, {users} or whatever with

$tables['settings'], $tables['users'] or whatever.

 

Please be as clear as possible as it is very hard to troubleshoot regex without extremely clear communication about desired input and output.

 

In all honesty I don't know..

 

static function Execute($query)
	{
		$tables = self::$config['tables'];
		$subject='"SELECT * FROM `{settings}`"';
		//echo self::$config['tables']['settings'];
		echo $tables['settings'];
		$query = preg_replace('/"SELECT \* FROM `\{([^}]+)\}`"/', '"SELECT * FROM `".$tables[\'\1\']"', $subject);
		echo $query . "<br />";
}

 

is what I have right now. then I call Database::Execute("SELECT * FROM `{settings}`"); and it outputs this:

SELECT * FROM `{settings}`

Table 'sports_sports.{settings}' doesn't exist

 

Thank you for your help and patience thus far by the way.

[ragax]

1. In your code, you have an echo $query; Does it output the query string you expect?

In other words, the first question is:

Does the regex work according to the specs you specified?

You may have other problems (talking to the database), but first, we need to know: does the regex do what you wanted it to do?

 

2. We prepared a query string ($query) according to your specs using regex, and I have no idea if the syntax of the query itself is correct, I only looked at your specs. But you seem to be executing a different query altogether anyhow.

I was expecting to see something like:

 

$result=$db->query($query);

 

Not

Execute(a query completely unrelated to $query)

 

(The query method above assumes you have already created a database object, at its simplest form:

$db= new PDO ($dsn,$dbUser,$dbPass); 

You are probably using another database interface.)

 

[mrdhood]

1. In your code, you have an echo $query; Does it output the query string you expect?

In other words, the first question is:

Does the regex work according to the specs you specified?

You may have other problems (talking to the database), but first, we need to know: does the regex do what you wanted it to do?

 

No it's outputting what I inputted: "SELECT * FROM `{settings}`"

 

2. We prepared a query string ($query) according to your specs using regex, and I have no idea if the syntax of the query itself is correct, I only looked at your specs. But you seem to be executing a different query altogether anyhow.

I was expecting to see something like:

 

$result=$db->query($query);

 

Not

Execute(a query completely unrelated to $query)

 

(The query method above assumes you have already created a database object, at its simplest form:

$db= new PDO ($dsn,$dbUser,$dbPass); 

You are probably using another database interface.)

 

Execute($query): $query = "SELECT * FROM `{settings}`" Which is exactly what I told you it would be, I'm just trying to change {settings} to $tables['settings']

[ragax]

Can you please try an exact copy-paste on my code from the first post, as I don't want to go blind trying to see if there is a difference with yours:

 

$subject='"SELECT * FROM `{settings}`"';
$s=preg_replace('/"SELECT \* FROM `\{([^}]+)\}`"/', '"SELECT * FROM `".$tables[\'\1\']"', $subject);
echo $s;

 

Here is the output I get:

 

"SELECT * FROM `".$tables['settings']"

 

Please let me know if you do not get that.

 

[ragax]

Also, I see in the output string the the string continuation dot and the `"grave accent" are missing, so you can change the pattern to this:

$s=preg_replace('/"SELECT \* FROM `\{([^}]+)\}`"/', '"SELECT * FROM `".$tables[\'\1\']."`', $subject);

 

Keep the echo and tell me if you get this output:

"SELECT * FROM `".$tables['settings']."`

 

 

[mrdhood]

Ok I see the issue: yes it's outputting "$tables['settings']" but I need it to output the actual value.

[mrdhood]

SELECT * FROM `{settings}` is the result of that echo with the regex from the last post.

[ragax]

yes it's outputting "$tables['settings']"

 

Great. So the expression is working.

 

SELECT * FROM `{settings}` is the result of that echo

My echo is

"SELECT * FROM `".$tables['settings']."`

 

Maybe a copy-paste problem? The main thing is that the first one works. Starting from there, you can introduce the dot (.) and the grave (`) into the expression that works, in the places where I had them, in order to get around the problem.

[PFMaBiSmAd]

To actually replace your {name} placeholder in the string with the contents of a php variable, you must use the /e modifier.

 

 

[mrdhood]

$query = preg_replace('/{(.*?)}/e', '$tables[\'$1\']', $query);

worked. thank you

[iwpg]

$query = preg_replace('/{(.*?)}/e', '$tables[\'$1\']', $query);

worked. thank you

 

 

And here we go :-) Deprecated: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead

 

This is killing me. I was confused, finally got the hang of the good ol preg_replace function, and now the "e" modifer requires a callback.

 

I am using an older CMS system that is no longer supported, so what this line of code actually accomplishes is beyond me. This is what is making this more difficult for me. My guess is that it allows PHP code to execute inside a template.

 

This is what I have originally, any help to get this translated to preg_replace_callback will be so much appreciated!

$template = preg_replace("/\?".">(\r*\n*.*)(<\?php|<\?)/esiU","addtemplateslashes('\\1')",$template);

Edited November 25, 2013 by iwpg

[iwpg]

This is what I have so far, but I don't know what to do with addtemplateslashes

	if (!function_exists('parseTagsRecursive')) {
		function parseTagsRecursive($template) 
		{
			
			$regex = '#\/\?".">(\r*\n*.*)(<\?php|<\?)/esiU#';

			if (is_array($template)) {
				$template = $template[1];
			}

			return preg_replace_callback($regex, 'parseTagsRecursive', $template);
		}
	}
$template = parseTagsRecursive($template);

[iwpg]

Please delete my last 2 posts. The thread was marked as answered. New post is located at http://forums.phpfreaks.com/topic/284259-preg-replace-callback-help/