[SOLVED]QRegExp is too greedy...

ThaRez

Hello
I have a QString, "data" that contains the source of a web page. Included in this is the following line:

@<iframe width="640" height="360" src="http://www.mysite.com/embed/4Ieelwhw" frameborder="0" allowfullscreen></iframe>@

I'm trying to extract the path that the src attribute equals to using a regexp. What I'm doing is the following:

@QRegExp regx("<iframe .src="(.)(".></iframe>)"); //<b>[^<]</b>
regx.setMinimal(true);
regx.indexIn(strType);

    qDebug() << strType.mid(regx.pos(1),regx.pos(2)-regx.pos(1));@

My problem is that the regex is too "greedy" though the setMinimal is set to true... The output in the debug output is:

"http://www.mysite.com/embed/4Ieelwhw" frameborder="0"

How can I make it stop at the first " and not include the frameborder? Thanks

-RS

JohanSolo

I think the '?' character in your regex disables the greedy mode.

tobias.hunger

!I have not tested this!

You could also try: "src="([^"]*)".

That is src=" followed by any character that is not a ".

ThaRez

Unfortunately neither suggestion helped...

I tried:

@QRegExp regx("<iframe .src="([^\”])(".*></iframe>)");
regx.setMinimal(true);
regx.indexIn(strType);

    qDebug() << strType.mid(regx.pos(1),regx.pos(2)-regx.pos(1));@

But the output is the same:

“http://www.mysite.com/embed/4Ieelwhw” frameborder=“0”

I also tried:
@QRegExp regx("<iframe .src="(.?)(".></iframe>)");
QRegExp regx("<iframe .src="(.?)(".></iframe>)");@
But neither matched anything...

Any further suggestions? Thanks!
-RS

ThaRez

ok, found the problem (when I posted my reply) Apparently there was a copy paste issue: [^\”] vs [^"]*.

it now works with:

@QRegExp regx("<iframe .src="([^"])(".*></iframe>)");@

Thank you!
-RS

JohanSolo

I would rather write (don't know whether it works though):

QRegExp regx("&lt;iframe .*src=\"(.+?)(\".*&gt;&lt;/iframe>)");

Note the + instead of your *. + stands for at least one character and maybe more, whilst * stands for zero or one character.

[quote author="ThaRez" date="1340956318"]I also tried:
@QRegExp regx("<iframe .src="(.?)(".></iframe>)");
QRegExp regx("<iframe .src="(.?)(".></iframe>)");@
But neither matched anything...

Any further suggestions? Thanks!
-RS

[/quote]