README

StringBuffer is a PHP class providing operations for efficient string buffering. It can hold a mix of plain strings and file contents, and treats them uniformly as a single continuous buffer.

Installation

composer require atk14/string-buffer

Basic usage

$sb = new StringBuffer();
$sb->addString("Hello World!\n");
$sb->addString(" How are you?");
$sb->addFile("/path/to/file");

$length = $sb->getLength();
$sb->printOut();

You can also pass an initial string to the constructor:

$sb = new StringBuffer("Hello World!");

Combining buffers:

$sb1 = new StringBuffer("Hello");
$sb2 = new StringBuffer(" World!");
$sb1->addStringBuffer($sb2);
echo $sb1; // "Hello World!"

Converting to string:

$string = (string)$sb;
// or
$string = "$sb";
// or
$string = $sb->toString();

Other operations:

// Replace a substring throughout the buffer
$sb->replace("World", "PHP");

// Extract a portion of the buffer (works like PHP's substr())
$part = $sb->substr(0, 5);
$last = $sb->substr(-3);

// Write the whole buffer to a file
$sb->writeToFile("/path/to/output.dat");

// Clear the buffer
$sb->clear();

Memory-efficient temporary buffer

StringBufferTemporary is a drop-in replacement for StringBuffer that automatically offloads content to a temporary file once it exceeds 1 MB. This keeps memory consumption low when working with large amounts of data.

$buffer = new StringBufferTemporary();

$buffer->add($megabyte);
$buffer->add($megabyte);
$buffer->add($megabyte);

$buffer->printOut();
// or
$buffer->writeToFile($target_filename);

Temporary files are created automatically and deleted when the buffer object is destroyed.

The threshold can be adjusted if needed:

StringBufferTemporary::$FILEIZE_THRESHOLD = 512 * 1024; // 512 kB

The temporary directory defaults to the system temp dir. To override it, define the TEMP constant before using the class:

define("TEMP", "/path/to/temp/");

Append buffer contents to the file

The file opening mode can be passed as the second parameter of the writeToFile() method.

// Write at the end of the file
$buffer->writeToFile("/path/to/output.dat","a"); 

Licence

StringBuffer is free software distributed under the terms of the MIT license