how to get only the specific content from a file using PHP. - php

Question

how to get only the specific content from a file using PHP.
I have a file with content:
reference 1.pdb
mobile 4r_1.pdb
ignore
fit
mobile 4r_10.pdb
ignore
fit
mobile 4r_22220.pdb
ignore
fit
Now, I want to take all the names i.e. (output)
4r_1
4r_10
4r_22220
in an array and print it.
The program i have written in php doesn't work properly, can have a look
$data = file_get_contents('file.txt'); // to read the file
$convert = explode("\n", $data); // take it in an array
$output4 = preg_grep("/mobile/i",$convert); //take only the line starts with mobile and put it in an array
if ($output4 !="/mobile/i")
{
print $output4;
print "\n";
}
Please help! to extract only the names

Answer 1

Try this:
$convert = explode("\n", $data); // take it in an array
$filenames = array();
foreach ($convert as $item) {
if(strstr($item,'mobile')) {
array_push($filenames,preg_replace('/mobile[\s]?([A-Za-z0-9_]*).pdb/','${1}',$item));
}
}
Now all the file names (assuming they are file names) are in the array $filenames

Answer 2

preg_grep returns an array of matching lines, your condition is treating $output4 as a string.
Loop over the array to print out each line and use either substr or str_replace to remove the unwanted characters from the string
$data = file_get_contents('test.txt'); // to read the file
$convert = explode("\n", $data); // take it in an array
$output4 = preg_grep("/mobile/i",$convert); //take only the line starts with mobile and put it in an array
foreach($output4 as $entry) {
print str_replace("mobile ", "", $entry) . "\n";
}

Answer 3

Below code should work:
$data = file_get_contents('file.txt'); // to read the file
$convert = explode("\n", $data); // take it in an array
$output4 = preg_grep("/mobile/i",$convert);
if (count($output4))
{
foreach ($output as $line) {
print $line; // or substr($line, 6) to remove mobile from output
print "\n";
}
}
Note:
Instead of doing
$data = file_get_contents('file.txt'); // to read the file
$convert = explode("\n", $data); // take it in an array
You may read a file into array with file() function:
$convert = file('file.txt'); // to read the file

Answer 4

Try this:
$content = file_get_contents('file.txt');
$lines = explode("\n", $content);
foreach ($lines as $line) {
if (preg_match('/^mobile\s+(.+)$/', $line, $match)) {
echo $match[1], "\n";
}
}