PHP file_get_contents(): Read file into a string

The PHP file_get_contents() function is used when we need to read a file into a string. For example:

<?php
   $mystr = file_get_contents("codescracker.txt");
   echo $mystr;
?>

The output of the above PHP example using the file_get_contents() function is:

Following is a snapshot of the opened file codescracker.txt, along with the current directory:

PHP Read File into String Preserving Newline or LineBreak

As you can see in the snapshot of the file codescracker.txt and the output shown above, the file contains text spread over three lines. But the output produced by the previous example, after getting the content of the file into a string, ignored all newline characters. Therefore, nl2br() comes into play. Here is an example:

<?php
   $mystr = file_get_contents("codescracker.txt");
   $mystr = nl2br($mystr);
   echo $mystr;
?>

Or

<?php
   $mystr = file_get_contents("codescracker.txt");
   echo nl2br($mystr);
?>

Both the examples above will produce the same output, which should be:

PHP file_get_contents() Syntax

The syntax of the file_get_contents() function in PHP is:

file_get_contents(path, include_path, context, start, length)

The first parameter (path) is required, whereas all three other parameters are optional.

Note: The include_path parameter is used when we need to search the file in the include_path (in php.ini). To do this, we need to specify this parameter as 1.

Note: The context parameter is used to specify the context in which to handle the file.

Note: The start parameter is used when we need to read a file into a string from any particular position. Negative values will be used to read from the specified position, from the end.

Note: The length parameter is used when we need to read a file into a string up to the specified maximum length of characters.

Advantages of the file_get_contents() function in PHP

• It only takes one line of code to use this function to read a file's contents into a string.
• This function reads the entire contents of the file into memory at once rather than line by line, making it very efficient.
• This function can be used to read the content of files that are accessible via a URL or stored on distant servers.
• If there are problems accessing the file or URL, this function provides thorough error messages.

Disadvantages of the file_get_contents() function in PHP

• This function reads the entire file's contents into memory, which can be problematic for large files or systems with limited memory.
• If this function is used to read files controlled by the user or to access potentially malicious URLs, it can pose a security risk.
• This function may cause performance issues if used to read large files or if the network connection fails when accessing remote files.
• Although this function generates detailed error messages, it is not always clear what action should be taken to resolve the issue.

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