mysql插入如何转义斜线？

Question

This is answered everywhere and I simply can't see what's wrong with my code:

print 'https://www.facebook.com/someURL'.'<br />';
print addslashes('https://www.facebook.com/someURL').'<br />';
print mysql_real_escape_string('https://www.facebook.com/someURL').'<br />';

Output is:

https://www.facebook.com/someURL
https://www.facebook.com/someURL
https://www.facebook.com/someURL

Why are no slashes being added in any of these cases?

Answer 1

Why are no slashes being added in any of these cases?

You don't have any characters that need escaping in that string.

---

That said, addslashes is not suitable and mysql_real_escape_string (like all of mysql_ ) is obsolete , you should use a modern replacement and use prepared statements / bound arguments instead of manual string escaping.

Answer 2

Because addslashes() returns a string with backslashes before characters that need to be escaped. These characters are single quote ('), double quote ("), backslash () and NUL (the NULL byte).

and your string doesnot contain any of the above mentioned characters.

Answer 3

From http://uk3.php.net/addslashes :

Returns a string with backslashes before characters that need to be escaped. These characters are single quote ('), double quote ("), backslash () and NUL (the NULL byte).