How to use php fread() function

php The fread() function is used to read an open file. You can read data of a specified length from the file. It will stop when length bytes are read or the end of the file (EOF) is read. Read and return the read string; syntax "fread($handle,$length)".

The operating environment of this tutorial: Windows 7 system, PHP version 7.1, DELL G3 computer.

PHP fread() function

fread() function reads an open file.

The fread() function in PHP can read data of a specified length in an open file and can also be used safely for binary files. When opening a file on a system that distinguishes between binary files and text files (such as Windows), add b to the mode parameter of the fread() function. The syntax format of this function is as follows:

fread($handle,$length)

where $handle is the file resource created by the fopen() function; $length is the maximum read of $length bytes.

fread() function can read data of a specified length from a file. When $length bytes are read or the end of file (EOF) is read, the function will stop reading and return the read The string obtained. Returns FALSE if the read fails.

Note that the fread() function will read from the current position of the file pointer. Use ftell() to find the current position of the pointer, and use rewind() to rewind the pointer position.

[Example] Use the fread() function to read the contents of the file and output it.

<?php
header("Content-type:text/html;charset=utf-8");
$filename = "test.txt";
$handle = fopen($filename, "r");
$contents = fread($handle, &#39;27&#39;);
echo &#39;从文件中读取 27 个字符长度：&#39;.$contents.&#39;<br>&#39;;
rewind($handle);
$contents = fread($handle, filesize($filename));
echo &#39;读取全部的文件内容：&#39;.$contents;
fclose($handle);
?>

The running results are as follows:

#The above example uses a filesize() function, its function is to obtain the file size, in the fread() function The function is to read the entire file.

Recommended learning: "PHP Video Tutorial"

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