how to send text using form post method when it has special characters

[student]

Hello,
I have some text files and they have many special characters.
I need to read the text in each file using
$handle = @fopen($filename, "r")
....
fread($handle, 1024000);
....
$content=urlencode($content);
...

Then, I am sending this to a form using post method using CURL.

Every file that doesn't have special characters is getting submitted without any problem.
However, when there are some special characters like

™
®
©

The form is not getting submitted.

I have tried to use this code :
$search = array("‘", "’", "'", "—", "”", "“", "…", "™", "®", "©");
$content = str_replace($search, "", $content);

But there are many more symbols and characters as i open new files.

So, please help me deal with these special characters.

Or, I think I need to encode these special characters into UTF-8
Please inform me how to do it.

Thank you.

[scrappy]

I think I need to encode these special characters into UTF-8
Please inform me how to do it.

string utf8_encode ( string $data ) ? Although I would encode the form encoding engine to be suitable, or rawurlencode() if your doing it yourself.

I don't know what your using CURL for, but I prefer to use XMLHttpRequest via Javascript, which is built into many web browsers (except IE6 and earlier, in which you have to use ActiveX). This way I can dynamically update the form as the user sees it (They got the main part of the page, followed shortly by the other parts).