Php read specific line from file

I'm trying to read a specific line from a text file using php. Here's the text file:

foo  
foo2

How would I get the content of the second line using php? This returns the first line:

..but I need the second.

Any help would be greatly appreciated

asked Apr 25, 2011 at 5:22

$myFile = "4-24-11.txt";
$lines = file[$myFile];//file in to an array
echo $lines[1]; //line 2

file — Reads entire file into an array

Blender

280k52 gold badges426 silver badges487 bronze badges

answered Apr 25, 2011 at 5:25

7

omg I'm lacking 7 rep to make comments. This is @Raptor's & @Tomm's comment, since this question still shows up way high in google serps.

He's exactly right. For small files file[$file]; is perfectly fine. For large files it's total overkill b/c php arrays eat memory like crazy.

I just ran a tiny test with a *.csv with a file size of ~67mb [1,000,000 lines]:

$t = -microtime[1];
$file = '../data/1000k.csv';
$lines = file[$file];
echo $lines[999999]
    ."\n".[memory_get_peak_usage[1]/1024/1024]
    ."\n".[$t+microtime[1]];
//227.5
//0.22701287269592
//Process finished with exit code 0

And since noone mentioned it yet, I gave the SplFileObject a try, which I actually just recently discovered for myself.

$t = -microtime[1];
$file = '../data/1000k.csv';
$spl = new SplFileObject[$file];
$spl->seek[999999];
echo $spl->current[]
    ."\n".[memory_get_peak_usage[1]/1024/1024]
    ."\n".[$t+microtime[1]];
//0.5
//0.11500692367554
//Process finished with exit code 0

This was on my Win7 desktop so it's not representative for production environment, but still ... quite the difference.

answered Jul 5, 2015 at 21:46

nimmneunnimmneun

1,10914 silver badges16 bronze badges

2

If you wanted to do it that way...

$line = 0;

while [[$buffer = fgets[$fh]] !== FALSE] {
   if [$line == 1] {
       // This is the second line.
       break;
   }   
   $line++;
}

Alternatively, open it with file[] and subscript the line with [1].

answered Apr 25, 2011 at 5:25

alexalex

467k197 gold badges865 silver badges975 bronze badges

2

I would use the SplFileObject class...

$file = new SplFileObject["filename"];
if [!$file->eof[]] {
     $file->seek[$lineNumber];
     $contents = $file->current[]; // $contents would hold the data from line x
}

answered Feb 25, 2016 at 21:15

PhilPhil

3,9498 gold badges58 silver badges103 bronze badges

1

you can use the following to get all the lines in the file

$handle = @fopen['test.txt', "r"];

if [$handle] { 
   while [!feof[$handle]] { 
       $lines[] = fgets[$handle, 4096]; 
   } 
   fclose[$handle]; 
} 


print_r[$lines];

and $lines[1] for your second line

Snake Eyes

15.8k32 gold badges107 silver badges208 bronze badges

answered Apr 25, 2011 at 5:32

balanvbalanv

10.5k27 gold badges90 silver badges137 bronze badges

1

$myFile = "4-21-11.txt";
$fh = fopen[$myFile, 'r'];
while[!feof[$fh]]
{
    $data[] = fgets[$fh];  
    //Do whatever you want with the data in here
    //This feeds the file into an array line by line
}
fclose[$fh];

answered Apr 25, 2011 at 5:27

PhoenixPhoenix

4,4181 gold badge19 silver badges13 bronze badges

2

This question is quite old by now, but for anyone dealing with very large files, here is a solution that does not involve reading every preceding line. This was also the only solution that worked in my case for a file with ~160 million lines.

It works by opening the file without reading anything, then moving the pointer instantly to a random position, reading up to 4096 characters from that point, then grabbing the first complete line from that data.

answered Dec 19, 2016 at 2:54

cantelopecantelope

1,1277 silver badges9 bronze badges

If you use PHP on Linux, you may try the following to read text for example between 74th and 159th lines:

$text = shell_exec["sed -n '74,159p' path/to/file.log"];

This solution is good if your file is large.

answered Oct 12, 2015 at 11:42

minerootmineroot

1,58715 silver badges23 bronze badges

1

You have to loop the file till end of file.

  while[!feof[$file]]
  {
     echo fgets[$file]. "
";
  }
  fclose[$file];

answered Apr 25, 2011 at 5:25

RikeshRikesh

25.8k14 gold badges77 silver badges86 bronze badges

0

You could try looping until the line you want, not the EOF, and resetting the variable to the line each time [not adding to it]. In your case, the 2nd line is the EOF. [A for loop is probably more appropriate in my code below].

This way the entire file is not in the memory; the drawback is it takes time to go through the file up to the point you want.

answered Nov 3, 2015 at 1:07

I like daggett answer but there is another solution you can get try if your file is not big enough.

$file = __FILE__; // Let's take the current file just as an example.

$start_line = __LINE__ -1; // The same with the line what we look for. Take the line number where $line variable is declared as the start.

$lines_to_display = 5; // The number of lines to display. Displays only the $start_line if set to 1. If $lines_to_display argument is omitted displays all lines starting from the $start_line.

echo implode['', array_slice[file[$file], $start_line, lines_to_display]];

answered Nov 28, 2015 at 15:17

drugandrugan

7208 silver badges10 bronze badges

I searched for a one line solution to read specific line from a file. Here my solution:

echo file['dayInt.txt'][1]

answered Jan 27, 2021 at 17:44

How read a specific line from a file in PHP?

Which of the following is the correct way to open read text file in PHP?