= 5.1.0, PHP 7, PHP 8)SplFileObject::ftruncate — Truncates the file to a given length說明public SplFileObject::ftruncate">

SplFileObject::ftruncate

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

SplFileObject::ftruncateTruncates the file to a given length

說明

public SplFileObject::ftruncate(int $size): bool

Truncates the file to size bytes.

參數(shù)

size

The size to truncate to.

注意:

If size is larger than the file it is extended with null bytes.

If size is smaller than the file, the extra data will be lost.

返回值

成功時(shí)返回 true, 或者在失敗時(shí)返回 false。

范例

示例 #1 SplFileObject::ftruncate() example

<?php
// Create file containing "Hello World!"
$file = new SplFileObject("/tmp/ftruncate""w+");
$file->fwrite("Hello World!");

// Truncate to 5 bytes
$file->ftruncate(5);

// Rewind and read data
$file->rewind();
echo 
$file->fgets();
?>

以上例程的輸出類似于:

Hello

參見

  • ftruncate() - 將文件截?cái)嗟浇o定的長(zhǎng)度