正则表达式动态格式

Question

Can some one help me in checking a sting using regular expression:

My String will be in any format lets see

12AAA22TBI

The above Sting is in a format of NNTTTNNTTT

Where

N - Number, T - TEXT

I am able to write a code to check the format in static. But the format will come dynamic.

Suppose the second case might be 123456TTT = NNNNNNTTT The Format will be different. Can some one help me to write a regular express with dynamic value;

Note: The length of the string as well as the length of the FORMAT will Change.

Pseudo code:

Function ('FORMAT','STRING'){
IF(FORMAT == STRING): Return 1;
ELSE Return 0;
}

FORMAT == STRING Here I need help to check the Format and string using regular expression but dynamically.

Example: My Function will be same but the Format and String will differ:

1. NNNTTTNN -- 111ABC22
2. TNTNTNTN -- A1B2C3D4
3. TTTTNNNNN -- ABCD12345
4. TTNNTTTTTT -- AB01ABCDEF

The above is some of the examples.

Answer 1

Use the example code below as a start...

$format = 'NNTTTNNTTT';
$value  = '12AAA22TBI';

$format = preg_replace('/[^NT]/', '', $format);
$format = preg_replace('/T/', '[A-Z]', $format);
$format = preg_replace('/N/', '\d', $format);
$format = "/^$format$/";

$match = (preg_match($format, $value));

print "$match\n";

Test it here .

Answer 2

I created a simple function that generates a regex, you could simply add rules to support other characters and map them to a specific regex:

function generateRegex($input){
    $rules = array(
        'N' => '[0-9]',
        'T' => '[a-zA-Z]',
        // You could add more rules here
    );
    $delimiter = '~';

    $output = strtr($input, $rules); // Replace-Fu
    $output = '^' . $output . '$'; // Add begin and end anchor, comment this line out if you don't want it.
    $output = $delimiter . $output . $delimiter; // Add the delimiters
    return $output; // Should I explain o_O ?
}

A demo :

$inputArr = array('NNNTTTNN','TNTNTNTN','TTTTNNNNN','TTNNTTTTTT');
foreach($inputArr as $input){
    echo $input . '->' . generateRegex($input) . '<br>';
}

Output:

NNNTTTNN -> ~^[0-9][0-9][0-9][a-zA-Z][a-zA-Z][a-zA-Z][0-9][0-9]$~
TNTNTNTN -> ~^[a-zA-Z][0-9][a-zA-Z][0-9][a-zA-Z][0-9][a-zA-Z][0-9]$~
TTTTNNNNN -> ~^[a-zA-Z][a-zA-Z][a-zA-Z][a-zA-Z][0-9][0-9][0-9][0-9][0-9]$~
TTNNTTTTTT -> ~^[a-zA-Z][a-zA-Z][0-9][0-9][a-zA-Z][a-zA-Z][a-zA-Z][a-zA-Z][a-zA-Z][a-zA-Z]$~