You want to read in only a little of the file at a time or to count the number of lines in a file.
Use fgets(). It returns a string of a certain length. Because it reads a line at a time, you can count the number of times it's called before reaching the end of a file.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="EN" lang="EN">
<head>
<title>Reading Files Incrementally</title>
<meta Name="Author" Content="Hann So">
</head>
<body>
<p>
<?php
if (isset($_POST['submit'])) {
process_form();
}
else {
display_form();// display form for the first time
}
function display_form() {
echo <<<HTML
<h2>Reading Files Incrementally</h2>
<form action = "$_SERVER[SCRIPT_NAME]" method="post">\n
Filename:
<input type="text" name="file" size="50"
value="http://voyager.deanza.edu$_SERVER[SCRIPT_NAME]" />
<br />
<input type="submit" name="submit" value="Submit" />
</form>
HTML;
}
function process_form() {
$lines = 0;
$file = "$_POST[file]";
echo "<font color=blue>";
// open the file for reading
if ($fh = fopen("$file", 'r')) {
// test for end of file on a file pointer with feof()
while (! feof($fh)) {
// get a line from the file
$s = fgets($fh);
echo htmlentities($s), "<br />";
if ($s) {
$lines++;
}
}
}
echo "</font>";
echo "<p>The file $file has $lines lines.</p>\n";
echo "<p><a href=\"$_SERVER[SCRIPT_NAME]\">Try again?</a></p>\n";
echo "<p><a href=\"example_l.php\">Do you want to write to the file?</a></p>\n";
}
?>
</p>
</body>
</html>
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