str_replace不能正常运行PHP

Question

I've got two strings that are lines pulled from a file. I'm trying to first strip them of their tags (like ) by doing a str_replace and replacing them with a space. Unfortunately, this doesn't seem to be working because when I echo out the results in the form I still see the tags.

Any ideas?

# Trim the title and description of their tags. Keep only text.
$title_new = $file_lines[$title_line];
str_replace("<title>"," ", $title_new);
str_replace("</title>"," ", $title_new);

$desc_new = $file_lines[$desc_line];
str_replace("<description>"," ", $desc_new);
str_replace("</description>"," ", $desc_new);

# Echo out the HTML form
echo "<form action=\"rewrite.php\" method=\"post\">";
echo "Title: <input type=\"text\" name=\"new_title\" size=\"84\" value=\"".$title_new."\">";
echo "</input>";

echo "<br>Article Body:<br>";
echo "<textarea rows=\"20\" cols=\"100\" wrap=\"hard\" name=\"new_desc\">".$desc_new."</textarea><br>";

echo "<input type=\"hidden\" name=\"title_line\" value=\"".$title_line."\">";
echo "<input type=\"hidden\" name=\"title_old\" value=\"".$file_lines[$title_line]."\">";
echo "<input type=\"hidden\" name=\"desc_line\" value=\"".$desc_line."\">";
echo "<input type=\"hidden\" name=\"desc_old\" value=\"".$file_lines[$desc_line]."\">";

echo "<input type=\"submit\" value=\"Modify\" name=\"new_submit\">";

Answer 1

 $title_new = str_replace(array("<title>", "</title>")," ", $file_lines[$title_line]);
 $desc_new = str_replace(array("<description>","</description>")," ", $file_lines[$desc_line]);

Or use

strip_tags