Question on using QRegularExpression

[leinad]

Hi!

I read a bunch of posts and read the docs but couldn't seem to find an answer to the issue I have.
In Qt 5 we were able to use QRegExp with a code fragment shown below
QRegularExpression digits("\d+"); // '\d+' (one or more digits)
QStringList attributeValues;

for(int i = 0; i < attributeValues.size(); i++)
{
if(digits.exactMatch(attributeValues[i]) && !attributeValues[i].contains(".")) //make sure floating point numbers are not included
{
intAttributeValues.append(attributeValues[i].toInt());
}
}

I'd like to implement the same logic using QRegularExpression
I know I can do something like this:
QRegularExpression digits(QRegularExpression::anchoredPattern("\d+"));

But how do implement an exact match as above with the if statement?

Any help would be appreciated!

[leinad]

@JonB Right, that makes sense. I think what I have is the same I just decided to add a boolean for simplicity :)

[leinad]

@leinad
I think I figure it out. Can someone please confirm if it makes sense?
QStringList attributeValues;
QRegularExpression digits(QRegularExpression::anchoredPattern("\d+"));

for(int i = 0; i < attributeValues.size(); i++)
{
QRegularExpressionMatch match = digits.match(attributeValues[i]);
bool intMatch = match.hasMatch();
if(intMatch && !attributeValues[i].contains("."))
{
intAttributeValues.append(attributeValues[i].toInt());
}
}

[JonB]

@leinad
It would be really helpful, for me at least, if you put blocks of code inside forum Code tags ( ``` ) .

[leinad]

I tried to figure out how to do that but couldn't find a way. Is this better?
I assume what I did makes sense?
Thanks!

QStringList attributeValues;
QRegularExpression digits(QRegularExpression::anchoredPattern("\d+"));

for(int i = 0; i < attributeValues.size(); i++)
{
    QRegularExpressionMatch match = digits.match(attributeValues[i]);
    bool intMatch = match.hasMatch();
    if(intMatch && !attributeValues[i].contains("."))
    {
        intAttributeValues.append(attributeValues[i].toInt());
    }
}

[JonB]

@leinad
Firstly, you know that your "\d+" is wrong in both cases (you may be getting away with it), it should always be "\\d+".

As you say: if (regExp.exactMatch()) needs to be translated to if (regularExpression.match(QRegularExpression::anchoredPattern("\\d+")).hasMatch()).

[leinad]

@JonB Thanks, I had a typo when I typed the code into this page. I do indeed have "\\d+"
In your logic you have
if (regularExpression.match(QRegularExpression::anchoredPattern("\\d+")).hasMatch())
but how do I check if my variable has attributeValues[i] has digits? It looks like my logic is correct I just broke it down into smaller code segments.

[JonB]

@leinad said in Question on using QRegularExpression:

but how do I check if my variable has attributeValues[i] has digits?

Sorry, I wrote the idea earlier but not the exact correct thing! Should be:

QRegularExpression digits(QRegularExpression::anchoredPattern("\\d+"));
for(int i = 0; i < attributeValues.size(); i++)
    if (digits.match(attributeValues[i]).hasMatch())

Is that what you mean?

[leinad]

@JonB Right, that makes sense. I think what I have is the same I just decided to add a boolean for simplicity :)