how to convert QString into int in qt creator

Question

I have seen one answer regarding to this same question but when I tried it with my problem it get confused.

here is my string,

bit_rate = "bitrate: 2334 kb/s"

I need to get the 2334 from this string and assign it into a integer variable.. how is this possible in qt creator. I tried toInt(), but it always gives 0 as the answer.

Solution 1

You need to get rid of the bitrate: prefix and kb/s suffix. The best way is to use QRegExp or QRegularExpression to extract the digit part of the string and then call toInt().

Here's example:

QString str = "bitrate: 3543 kb/s";
int value;

QRegExp re("bitrate:\\s*(\\d+)\\s*.*");
if (re.indexIn(str) != -1) {
    value = re.cap(1).toInt();
} else {
    qDebug() << "String not matched.";
    return;
}
qDebug() << value;

Solution 2

The reference page has a ton of material on this. The easiest way to implement this is to split the string based on spaces, then convert the one you want to an Int.

Example:

QString str = "bitrate: 3543 kb/s";
QStringList lst = str.split(" ");
Int value = lst[1].toInt();

Solution 3

QTextIStream stream("bitrate: 3543 kb/s");
QString prefix, sufix;
int result;
stream >> prefix >> result >> sufix;

Comments

[Mlarnt90]

thanx that exactly gave me the answer I wanted.

[Mlarnt90]

oops I was being silly. thanx ur answer gave me the result very easily..thank you very much.

[Eitan T]

@Mlarnt90 so the answer to duplicate question didn't help you? It's basically the same as this one.

[Mlarnt90]

thanx @Googie for your answer. Because of it, I tend to use regular expressions for other parts in my code.