如何使用PHP创建表单来更新文件？

Question

I have written a PHP script which allows me to modify and update a file on a webpage, which works, but the script right now presents the entire contents of the file in a text area. I would like to extract just the string from the file and pre-populate it in a form text field (instead of a text area).

Below are the two files I need to update. I would like to just update the IP addresses. So the form would ideally show that mail.helloworld.com current maps to "208.164.222.2" and populate that IP address in a form text field. Same idea for the /etc/postfix/main.cf file as shown below.

/etc/hosts

IPAddress Hostname Alias 127.0.0.1 localhost deep.openna.com 208.164.222.2 mail.helloworld.com mail 208.164.222.3 web.helloworld.com web

/etc/postfix/main.cf

relayhost= 192.168.1.10

===

Current working script using textarea:

<form action="<?php echo $PHP_SELF;?>" method="post">
<textarea rows="13" cols="110" name="content">
<?
$fn = "/etc/postfix/main.cf";
print htmlspecialchars(implode("",file($fn)));

?> 
</textarea></br>
<input id= "relayhost_button" type="submit" value="Update"> 
</form> 



<?
$fn = "/etc/postfix/main.cf";
$content = stripslashes($_POST['content']);
$fp = fopen($fn,"w") or die ("Error opening file in write mode!");
fputs($fp,$content);
fclose($fp) or die ("Error closing file!");
echo "<meta http-equiv=\"refresh\" content=\"0; url=done.php\" />
";
?>

Here is the current textarea based form:

New text field based form I want:

As always, thanks folks!

Answer 1

Parse the file, then present the wanted line to the user. Once (s)he has edited it, reparse the file, and replace the information. (Instead of parsing, you could just track which line number it was.)

Other than that, the question gets a bit in depth. Do you have any specific problems?

Also, a few non-related suggestions:

• Replace the implode(file()) with file_get_contents.
• Use complete opening tags ('< ?php' without the space)
• Use fwrite instead of fputs (no actual justification for this one, I just avoid using aliases)
• A large part personal preference, but I find it cleaner to do redirects with headers than with meta tags.

Eg:

header("Location: http://blah/done.php");