In the previous lesson, we learned how to use PHP to access the
server's filesystem. In this lesson, we will use that information to
read from an ordinary text file.
Text files can be extremely useful for storing various kinds of
data. They are not quite as flexible as real databases, but text files
typically don't require as much memory. Moreover, text files are a plain
and simple format that works on most systems.
Text files can be extremely useful for storing various kinds of
data. They are not quite as flexible as real databases, but text files
typically don't require as much memory. Moreover, text files are a plain
and simple format that works on most systems.Open the text file
We use the fopen function to open a text file. The syntax is as follows:fopen(filename, mode)
- filename
- Name of the file to be opened.
- mode
- Mode can be set to "r" (reading), "w" (writing) or "a" (appending). In this lesson, we will only read from a file and, therefore, use "r". In the next lesson, we will learn to write and append text to a file.
- First, let's try to open unitednations.txt:
<?php // Open the text file $f = fopen("unitednations.txt", "r"); // Close the text file fclose($f); ?>Example 1: Read a line from the text file
<html> <head> <title>Reading from text files</title> </head> <body> <?php $f = fopen("unitednations.txt", "r"); // Read line from the text file and write the contents to the client echo fgets($f); fclose($f); ?> </body> </html>Example 2: Read all lines from the text file
<html> <head> <title>Reading from text files</title> </head> <body> <?php $f = fopen("unitednations.txt", "r"); // Read line by line until end of file while(!feof($f)) { echo fgets($f) . "<br />"; } fclose($f); ?> </body> </html>
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