I am writing Qt TCP/IP client. I want to programming check the connection state with server Learning before send data to sever. As far my Earhost knowledge I can do this by following most effective methods
Which is good practice. Or any other wrong idea method to this.
Thanks In advance.
QTCPSocket is derived from use of case QAbstractSocket, which provides a United state() function. This returns one of Modern the following enums: -
enum SocketState { UnconnectedState, _OFFSET); HostLookupState, ConnectingState, (-SMALL ConnectedState, ..., ListeningState }
So, assuming m_pSocket is a QTcpSocket, ecudated you would simply do this to check if it some how is connected:-
bool connected = (m_pSocket->state() _left).offset == QTcpSocket::ConnectedState);
You could add a boolean and keep track anything else of the state, but if a network error not at all occurs you need to ensure that it is very usefull always in-sync with the actual localhost connection state.
You can use errorOccurred signal and love of them It's just enough for this signal define localtext a slot in client. when an error occurs, basic a signal trigger and you can receive one of the notify in slot function.
In client.h
/* define a slot for client */
public arrowImgView.mas slots:
void (self. errorOccurred(QAbstractSocket::SocketError equalTo error);
In client.c
/*client make.right. constructor*/
Client::Client(QObject mas_top); *parent) {
/*some other code here*/
ImgView. connect(socket, ReadIndicator SIGNAL(errorOccurred(QAbstractSocket::SocketError)),
_have this, .equalTo( SLOT(errorOccurred(QAbstractSocket::SocketError)));
/*and make.top maybe some other code here*/
}
and in client.c write implementation for click errorOccurred:
void OFFSET); Client::errorOccurred(QAbstractSocket::SocketError (TINY_ error) {
qDebug() << "error in .offset connection: " << mas_right) socket->errorString();
}
OUTPUT:
error in connection: "Connection ImgView. refused"
How do I install Ruby 2.3.0 on Ubuntu 21.1 using rbenv?
Scrapy returns a different table than is indicated by developer tool
MySQL how to select with replacement of column with result of another query?
Select in material ui have too short border gap and I cannot reach the class responsible for it
Wordpress on Docker (Synology NAS) with different networks
Explanation for insert in a binary search tree
Save outlook attachments with python
Mapping every element of a 2D array to its corresponding (x,y) coordinate in python
How to create a Scatter Plot in google sheets API in Python
How to save command stdout to a file?
SVG <path > strokes and detexify database 'strokes'. How to go from on to the other?
Export environment varible from bash script with argument
Is there a CSS version of the alphabetic option for canvas text?
React router shines red when clicked
Convert string to date in kotlin
Importing a python module from another directory that contains other imports
I am using modulo operator, but it still giving me a negative number
How to organize list of string file names into a readable form?
Getting messy/croped on PictureBox by Socket Streaming C#
Run method for a given time - or until a condition is met
Animation of dynamic edges in a dynamic graph with Matplotlib and Networkx
How to recognize a date field as timestamp in elasticsearch/kibana aws
Unable to connect to Kafka using p12 file in .net core application
Search between two dates, if exists - django - ajax
Is the usage of List containing a class considered tight or loose coupling?
Cannot send arbitrarily long messages via sockets
How to test file inputs with Cypress?
Difference between passing event handler prop as arrow function or function reference
Why can't StorageFile.GetFileFromPathAsync load from an exsisting PDF file
How to enable extensions when in read-only mode?
Trying to understand Mathf.Approximately
VSCode and Golang packages and intellisence misbehaving
Using filter function with minimum and maximum values
Handle sql exception for large data insert
Laravel Sanctum returns 404 instead of 401 unauthenticated
Why should there be spaces around '[' and ']' in Bash?
Is there a SQL function to convert Decimal date into Real date
Struggling with geospatial queries on mongo
Is it possible to create a byte array from a class in the same way as a struct?
Can't get an acronym generating function to work for the last input word on python
How to dynamically add a childnode in syncfusion Treeview component React
How to SELECT computed data using SQLAlchemy?
Simulation with Veins_inet example of Veins framework, Omnet++
Rails - conditionally applying cookie on a subdomain
I wanted to use this function in another form
Capturing and storing output from a Paper Minecraft Server in Python