DateTimeFromStringPerfTest.pro

#-------------------------------------------------
#
# Project created by QtCreator 2010-11-20T18:00:03
#
#-------------------------------------------------

QT       += core

QT       -= gui

TARGET = DateTimeFromStringPerfTest
CONFIG   += console
CONFIG   -= app_bundle

TEMPLATE = app


SOURCES += main.cpp

HEADERS += \
    QCachingLocale.h

main.cpp

#include <QDateTime>
#include <QTime>
#include <QTextStream>
#include <QDebug>
#include "QCachingLocale.h"

#define NUM_CALLS 1000

void parseDate(QTextStream & cout) {
    QTime timer;
    timer.start();

    for (int i = 0; i < NUM_CALLS; i++)
        QDateTime::fromString("16-Nov-2010 16:10:00", "dd-MMM-yyyy HH:mm:ss");

    cout << timer.elapsed() << " ms were necessary for parsing the date " << NUM_CALLS<< " times." << endl;
}

int main(int argc, char *argv[]) {
    QTextStream cout(stdout);

    cout << "Without QCachingLocale:" << endl;
    parseDate(cout);

    cout << endl << "With QCachingLocale:" << endl;
    QCachingLocale cl;
    parseDate(cout);

    return 0;
}

output

Without QCachingLocale:
4839 ms were necessary for parsing the date 1000 times.

With QCachingLocale:
23 ms were necessary for parsing the date 1000 times.