SplFileObject::key

(PHP 5 >= 5.1.0, PHP 7)

SplFileObject::key — Get line number

说明

public SplFileObject::key ( void ) : int

Gets the current line number.

Note:

This number may not reflect the actual line number in the file if SplFileObject::setMaxLineLen() is used to read fixed lengths of the file.

参数

此函数没有参数。

返回值

Returns the current line number.

范例

Example #1 SplFileObject::key() example

 <?php
$file = new SplFileObject("lipsum.txt");
foreach ($file as $line) {
    echo $file->key() . ". " . $line;
}
?>

以上例程的输出类似于：

0. Lorem ipsum dolor sit amet, consectetur adipiscing elit. 
1. Duis nec sapien felis, ac sodales nisl. 
2. Lorem ipsum dolor sit amet, consectetur adipiscing elit.

Example #2 SplFileObject::key() example with SplFileObject::setMaxLineLen()

 <?php
$file = new SplFileObject("lipsum.txt");
$file->setMaxLineLen(20);
foreach ($file as $line) {
    echo $file->key() . ". " . $line . "\n";
}
?>

以上例程的输出类似于：

0. Lorem ipsum dolor s
1. it amet, consectetu
2. r adipiscing elit. 
3. 

4. Duis nec sapien fel
5. is, ac sodales nisl
6. . 

7. Lorem ipsum dolor s
8. it amet, consectetu
9. r adipiscing elit.

参见

SplFileObject::current() - Retrieve current line of file
SplFileObject::seek() - Seek to specified line
SplFileObject::next() - Read next line
SplFileObject::rewind() - Rewind the file to the first line
SplFileObject::valid() - Not at EOF