如何安全删除QT :: QTcpSocket？

Question

QTcpSocket * QTcpServer::nextPendingConnection () [virtual]

The socket is created as a child of the server, which means that it is automatically deleted when the QTcpServer object is destroyed . It is still a good idea to delete the object explicitly when you are done with it , to avoid wasting memory.

In my application, a QTcpServer lives for a long time (it disconnects from host when connection is closed but is never destroyed unless the program exits), and it accepts a lot of QTcpServer::nextPendingConnection and takes a lot of memory.

How should I delete the old QTcpSocket object before switching to the next pending one to save memory, while at the same time avoid double-delete?

Is delete ok in this case?

Answer 1

Is delete ok in this case?

Yes, thanks to the cleverness of Qt's object design.

In particular, QTcpSocket derives (eventually) from Object, and the QObject destructor method contains this code at the end:

if (d->parent)        // remove it from parent object
    d->setParent_helper(0);

So deleting the QTcpSocket object will automagically remove the QTcpSocket from the children-list of its parent object (in this case, the QTcpServer), so there will be no double-delete when the QTcpServer object is destroyed.