Search for a string in a txt file

I want to search for a string in a txt file and if there is one single match then should return the number from that line

Eg.

string1 22
string2 432
string3 324

Code (markup):

If I will seach for string3 it must return 324

I started with this code

$file="myfile.txt";
$Body= fopen( $file, 'r' );
$line=explode("\n", $Body); // takes every line

Code (markup):

Thank you in advance

 

Is the number being returned with the string the line number the string is found on or something else?

 

the number returned is found on that line where the string is found. Hope that make sense

 

This was the solution I wrote.

<?php
$body =file("test.txt");

while (list(, $value) = each($body)) {
	if( preg_match("/(string[0-9]+) ([0-9]+)/", $value, $matches)) {
		print "$matches[1] $matches[2] <br>";
	}
}
?>

Code (markup):

 

I will explain again .. your code display every values

I have this in a file

blabla 21
blablabla 23
bla 29
blablabla 3

Code (markup):

I want to search in this file for bla. If bla is found in this file should return the number 3. If I search for blablabla and is found should return 23 and so on.

 

It's pretty much the same code, with some tweaking

<?php
$body =file("test.txt");
$string = "bla";

while (list(, $value) = each($body)) {
	if( preg_match("/$string ([0-9]+)/", $value, $matches)) {
		print "$matches[1] $matches[2] <br>";
	}
}
?>

Code (markup):

 

Thank you for your help .. However is not what I want.. This script return all the numbers on a different line

21
23
29
3 

Code (markup):

And I want to return only the number from that line where is found $string = "bla";

 

$content = file_get_contents('file.txt');
$search_text = 'bla';

if(preg_match('%\b'.preg_quote($search_text).'\b\s(\d+)%', $content, $out)) {
  echo $out[1];
}else{
  echo 'No match found';
}

PHP: