DirectoryIterator::seek() Method is one of the PHP operations used in filesystem and stream workflows. Moves a DirectoryIterator to an integer position in the underlying iteration. The examples below show what it does and how to handle its result.
What Is DirectoryIterator::seek() Method?
Moves a DirectoryIterator to an integer position in the underlying iteration.
Its syntax is:
DirectoryIterator::seek(int $offset)
The parameters are:
int $offset— Byte offset or position from the chosen origin.
Return value: This method returns no value.
Important: Positions depend on directory enumeration and should not be treated as stable identifiers.
Example 1: Basic Usage
The basic example focuses on the behavior of DirectoryIterator::seek() Method: moves a DirectoryIterator to an integer position in the underlying iteration. Inputs are defined locally or shown as application-controlled paths.
<?php
$entries = new DirectoryIterator(__DIR__);
$entries->seek(0);
if ($entries->valid()) { echo $entries->getFilename(); }
The displayed value, file content or return status depends on the input and surrounding environment. Results involving local paths, identifiers or generated files are not fixed values.
Example 2: A Different Use Case
This second example illustrates another input or execution condition for DirectoryIterator::seek() Method. Notice the different checks, arguments, or output handling.
<?php
$entries = new DirectoryIterator(__DIR__);
$entries->seek(1);
if ($entries->valid() && !$entries->isDot()) { echo $entries->getFilename(); }
This variation matters because positions depend on directory enumeration and should not be treated as stable identifiers.
Practical Example: Using the Operation in an Application
The following example demonstrates how DirectoryIterator::seek() Method fits into a more complete file or archive workflow, including inputs and appropriate checks.
<?php
$iterator = new DirectoryIterator(__DIR__);
$targetPosition = 2;
$iterator->seek($targetPosition);
if ($iterator->valid() && $iterator->isFile()) { echo "Selected: " . $iterator->getFilename(); }
The operation shown is an illustrative script. Adapt the filenames, required permissions, and error handling to your own controlled application environment before running it.
Important Behavior and Edge Cases
- Function behavior: Moves a DirectoryIterator to an integer position in the underlying iteration.
- Limitation: Positions depend on directory enumeration and should not be treated as stable identifiers.
Comparison With Related Functions
| Function or Method | Difference |
|---|---|
DirectoryIterator::seek() Method | Moves a DirectoryIterator to an integer position in the underlying iteration. |
DirectoryIterator::next() | Advances one item instead of seeking to a requested index. |
Use DirectoryIterator::seek() Method for the specific behavior described above. The related operation, DirectoryIterator::next(), serves a different purpose; do not substitute it unless that different behavior is intended.
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Confusing iterator position, keys and returned values. | Positions depend on directory enumeration and should not be treated as stable identifiers. Verify cursor position and flags before reading or advancing entries. |
| Treating DirectoryIterator::next() as an interchangeable replacement for DirectoryIterator::seek() Method. | Advances one item instead of seeking to a requested index. |
Key Takeaways
- Moves a DirectoryIterator to an integer position in the underlying iteration.
- Positions depend on directory enumeration and should not be treated as stable identifiers.
- Related operation: DirectoryIterator::next() — Advances one item instead of seeking to a requested index.
DirectoryIterator::seek() Method is useful when its specific behavior matches your application requirement. Keep paths controlled, check failures, and handle environment-dependent operations deliberately.