match and replace multi pattern on php string with regex

Question

I have a code like this to find a pattern for example ##random_number_10## I need to take the number 10 to be used as a parameter in the function and that function will go to str_replace to replace the pattern

string :

ini subjek lur ##random_mix_5## ##random_string_up_10## ##random_number_15##

output :

ini subjek lur o1ovp HDBVPVJTYY 741007211142434

.

function replace ($sumber) {

        preg_match_all("/##random_number_(\d+)##/", $sumber, $match_number);
        preg_match_all("/##random_string_up_(\d+)##/", $sumber, $match_string_up);
        preg_match_all("/##random_string_low_(\d+)##/", $sumber, $match_string_low);
        preg_match_all("/##random_string_uplow_(\d+)##/", $sumber, $match_string_uplow);
        preg_match_all("/##random_mix_(\d+)##/", $sumber, $match_mix);

        $dari = [
            $match_number[0][0], 
            $match_string_up[0][0], 
            $match_string_low[0][0], 
            $match_string_uplow[0][0], 
            $match_mix[0][0]
        ];

        $ke   = [
            random_number($match_number[1][0]), 
            random_string_up($match_string_up[1][0]), 
            random_string_low($match_string_low[1][0]), 
            random_string_uplow($match_string_uplow[1][0]), 
            random_mix($match_mix[1][0])
        ];

        return str_replace($dari, $ke, $sumber);

    };

the problem is when I try to replace all of them an error will appear if the string does not contain one of the searches. is there another way to replace the pattern on the string?

dearsina · Accepted Answer · 2019-06-06 10:42:24Z

1

You're probably getting an Undefined offset notice because you're referencing an array key that doesn't exist:

$sumber = "ini subjek lur ##random_mix_5## ##random_string_up_10## ##random_number_15##";

preg_match_all("/##random_number_(\d+)##/", $sumber, $match_number);
preg_match_all("/##random_string_up_(\d+)##/", $sumber, $match_string_up);
preg_match_all("/##random_string_low_(\d+)##/", $sumber, $match_string_low);
preg_match_all("/##random_string_uplow_(\d+)##/", $sumber, $match_string_uplow);
preg_match_all("/##random_mix_(\d+)##/", $sumber, $match_mix);

var_dump($match_string_uplow[1][0]);

Will output: Notice: Undefined offset: 0 on line 11

A slightly hacky solution is to add a @ symbol before each value being sent. This will surpress the error message and simply return a NULL value:

var_dump(@$match_string_uplow[1][0]);

Will output: NULL

Now it could also be that your error is generated by the function you're calling if you don't submit it a value. In which case, the solution will depend on how strict your function is when defining values.

answered Jun 6, 2019 at 10:42

dearsina

5,2603 gold badges32 silver badges38 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Toto Over a year ago

@MukhlisAkbarrudin: Hide an error message is never a good idea.

dearsina Over a year ago

@Toto While I completely agree with you in principle, in this particular context, all you're hiding is an expected undefined offset notice. Frankly, most people turn off all notice level errors anyway, so it's not a huge crime to hide it here. However, I agree that it's not a good idea to make a habit out of the @ prefix.

Toto · Accepted Answer · 2019-06-06 10:45:10Z

Build the 2 arrays only if there is a match:

function replace ($sumber) {
    $dari = array();
    $ke = array();
    if (preg_match_all("/##random_number_(\d+)##/", $sumber, $match)) {
        $dari[] = $match[0];
        $ke[]   = $match[1]
    }
    if (preg_match_all("/##random_string_up_(\d+)##/", $sumber, $match)) {
        $dari[] = $match[0];
        $ke[]   = $match[1]
    }
    if (preg_match_all("/##random_string_low_(\d+)##/", $sumber, $match)) {
        $dari[] = $match[0];
        $ke[]   = $match[1]
    }
    if (preg_match_all("/##random_string_uplow_(\d+)##/", $sumber, $match)) {
        $dari[] = $match[0];
        $ke[]   = $match[1]
    }
    if (preg_match_all("/##random_mix_(\d+)##/", $sumber, $match)) {
        $dari[] = $match[0];
        $ke[]   = $match[1]
    }

    return str_replace($dari, $ke, $sumber);

};

Collectives™ on Stack Overflow

match and replace multi pattern on php string with regex

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related