LKBEN11148: Hoto read a text file and process each line with Qt


This article has not been checked!

LKB | Created: 02/04/2020 | Version: 0 | Language: EN | Rating: 0 | Outdated: False | Marked for deletion: False

Author: Wim Peeters - Keskon GmbH & Co. KG


Symptom

You need to process a big text file and do womething with each line

Cause

none

Solution

To read a text file and parse it into a text string you can use the following code:


     QFile file("in.txt");
     if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
         return;

     QTextStream in(&file);
     while (!in.atEnd()) {
         QString line = in.readLine();
         process_line(line);
     }

If you need to split the String (QString) into parts with a delimiter you can use the following code snippet:


     QString str = "a,,b,c";
     QStringList list1 = str.split(",");

About the Author

Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux in different European countries and different European languages. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform where he is one of the most important contributors and the main developer.

Disclaimer:

The information provided in this document is intended for your information only. Lubby makes no claims to the validity of this information. Use of this information is at own risk!