SplFileObject::__construct

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

SplFileObject::__construct — Construct a new file object

说明

public SplFileObject::__construct ( string $filename , string $mode = "r" , bool $useIncludePath = false , resource|null $context = null )

Construct a new file object.

参数

filename: The file to read.

Tip
如已启用fopen 包装器，在此函数中， URL 可作为文件名。关于如何指定文件名详见 fopen()。各种 wapper 的不同功能请参见支持的协议和封装协议，注意其用法及其可提供的预定义变量。
mode: The mode in which to open the file. See fopen() for a list of allowed modes.
useIncludePath: Whether to search in the include_path for filename.
context: A valid context resource created with stream_context_create().

返回值

没有返回值。

错误／异常

Throws a RuntimeException if the filename cannot be opened.

Throws a LogicException if the filename is a directory.

范例

Example #1 SplFileObject::__construct() example

This example opens the current file and iterates over its contents line by line.


<?php
$file = new SplFileObject(__FILE__);
foreach ($file as $line_num => $line) {
    echo "Line $line_num is $line";
}
?>

以上例程的输出类似于：

Line 0 is <?php
Line 1 is $file = new SplFileObject(__FILE__);
Line 2 is foreach ($file as $line_num => $line) {
Line 3 is     echo "Line $line_num is $line";
Line 4 is }
Line 5 is ?>

参见

SplFileInfo::openFile() - Gets an SplFileObject object for the file
fopen() - 打开文件或者 URL

User Contributed Notes

KEINOS at blog.keinos.com 22-May-2017 04:24


When using URL as a filename, such as "http://..." or "php://stdin", and also have the fopen wappers on, and you get a 'RuntimeException' error, try using "NoRewindIterator" class to a SplFileObject instance.



<?php

$url = 'http://sample.com/data.csv';

$file = new NoRewindIterator( new SplFileObject( $url ) );

foreach ($file as $line_num => $line) {

    echo "Line $line_num is $line";

}

?>



While opening a file, a rewind method will be called, but these URL iterators cannot be rewind, so you'll get a "Fatal error: Uncaught exception 'RuntimeException' with message 'Cannot rewind file ...'" error.

majna 20-Aug-2014 10:09


(PHP >= 5.3) If filename is a directory, a LogicException will be thrown: "Cannot use SplFileObject with directories"