How to specify file access and modification time in PHP?

This article will introduce to you how to specify the access and modification time of files in PHP. Then we can use PHP's built-in function touch() to achieve the settings.

The touch() function in PHP is a built-in function used to set the access and modification time of a specified file.

The file name of the file whose access and modification time must be set is sent as a parameter to the touch() function together with the time. True is returned on success and False on failure. If the file does not exist, it is created first. (Recommended: PHP Tutorial)

Syntax:

touch(filename, time, atime)

Parameters:

in PHP touch()The function accepts three parameters.

1. filename: This is a required parameter that specifies the filename of the file whose access and modification times must be changed.

2. #time: This is an optional parameter used to specify the time. By default, it takes the current system time.

3. atime: It is an optional parameter used to specify the access time. By default, if no parameter is set, the current system time is required.

Return value:

Returns True on success and False on failure.

Note:

1. Time resolution may vary from file system to file system, so unexpected results may sometimes occur.

2. The $time parameter in the touch() function has a future limit of approximately 1,000,000 seconds.

The following code example illustrates the touch() function.

Suppose there is a file named "gfg.txt"

Example 1:

<?php 
$file_pointer = "gfg.txt"; 
// 使用touch()函数将文件的修改时间更改为当前系统时间
if (touch($file_pointer))  
{ 
   echo ("$file_pointer 修改时间已设置为当前系统时间。"); 
}  
else 
{ 
   echo ("$file_pointer 修改时间无法更改"); 
}

Output :

gfg.txt 修改时间已设置为当前系统时间。

Example 2:

<?php 
$file_pointer = "gfg.txt"; 
  
$time = time() - 18000; 
  
// 使用touch()函数将文件的修改时间更改为当前系统时间
if (touch($file_pointer, $time))  
{ 
    echo ("$file_pointer 修改时间已经改为过去5小时。"); 
 }  
else 
{ 
   echo ("$file_pointer 修改时间无法更改"); 
}

Output:

gfg.txt修改时间已经改为过去5小时。

This article is about accessing and specifying files in PHP The method of modifying the time is introduced. I hope it will be helpful to friends who need it!

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