Date in File Name

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Date in File Name

In the case you have to build a file name after the current date, so that it will look like data_mm_dd_yyyy.txt you can use the following simple function to get the string name of the file.

QString FileNameHandler::todayFileName(){<br /> QDate today = QDate::currentDate();<br /> QString relativeFileName( &quot;data_&quot; );<br /> relativeFileName.append( QString::number( today.month() ) );<br /> relativeFileName.append( &quot;''&quot; );<br /> relativeFileName.append( QString::number( today.day() ) );<br /> relativeFileName.append( &quot;''&quot; );<br /> relativeFileName.append( QString::number( today.year() ) );<br /> relativeFileName.append( &quot;.txt&amp;quot; );<br /> return relativeFileName;<br />}

Or its shorter version that uses the overloading of the + operator for QString:

QString FileNameHandler::todayFileName(){<br /> QDate today = QDate::currentDate();<br /> QString relativeFileName( &quot;data_&quot; );<br /> relativeFileName + QString::number( today.month()<br /> + &quot;''&quot; + QString::number( today.day() )<br /> + &quot;''&quot; + QString::number( today.year() )<br /> + &quot;.txt&amp;quot;;

return relativeFileName;<br />}

The fastest - and clearest - version, without calling a custom function, is

QString filename = QDate::currentDate().toString(&quot;'data_'MM_dd_yyyy'.txt'&quot;);<code>

and when the files should get ordered chronological, then use
QString filename = QDate::currentDate().toString("'data_'yyyy_MM_dd'.txt'");</code>