SplFileObject::seek

(PHP 5 >= 5.1.0)

SplFileObject::seekSeek to specified line

Description

public void SplFileObject::seek ( int $line_pos )

Seek to specified line in the file.

Parameters

line_pos

The zero-based line number to seek to.

Return Values

No value is returned.

Errors/Exceptions

Throws a LogicException if the line_pos is negative.

Examples

Example #1 SplFileObject::seek() example

This example outputs the third line of the script which is found at position 2.

<?php
$file 
= new SplFileObject(__FILE__);
$file->seek(2);
echo 
$file->current();
?>

The above example will output something similar to:

$file->seek(2);

See Also

Коментарии

A sleek way of counting the number of lines in a file can be like below

$file = new \SplFileObject('file.extension', 'r');
$file->seek(PHP_INT_MAX);

echo $file->key() + 1;
2017-09-21 12:19:35
http://php5.kiev.ua/manual/ru/splfileobject.seek.html
there is a bug using fseek on previos versions of PHP8.0.1
See:

https://bugs.php.net/bug.php?id=46569

https://3v4l.org/O89dJ

I solved it with a function:

<?php
/**
* SEEK an Spl object
* There is a bug in php for seeking files
* seems solved php_version > PHP8.0.1
* See https://bugs.php.net/bug.php?id=46569
* & https://3v4l.org/O89dJ
*
* $Spl->seek() Works ok in all versions with offset 0 (first row)
* On PHP_VERSION < 8.0.1:
*  - Offset 1: seek() cannot seek at row 1. It will be done manually, rewind file and reading first row
*  - Rest of Offsets: The cursor remains at next row of $Offset
*
* @param SplObject $Spl
* @param int $Offset
*/

function seek_spl($Spl$Offset){
    if (
version_compare(PHP_VERSION'8.0.1''>=') || $Offset == 0) {
       
$Spl->seek($Offset);
    } else {
        if( 
$Offset == ){
           
$Spl->rewind(); // Ensure to go at first row before exit
           
$Spl->fgets(); // Read line 0. Cursor remains now at line 1
       
} else {
           
$Spl->seek($Offset-1);
        }
    }
}
?>
2021-08-26 15:02:56
http://php5.kiev.ua/manual/ru/splfileobject.seek.html

    Поддержать сайт на родительском проекте КГБ