Question about virtualWrite?

Hi

When hardware call virtualWrite, but hardware not connecting with Blynk server, will it automatically perform when connected to Blynk sever again? Example, I update status of button on app by virtualWrite, but when virtualWrite call, connection to Blynk server is droped, when connect again, will the status of button update?

no, it will not be automatically updated.
But you can handle this in BLYNK_CONNECTED() { ... } handler.
Please note, that it is is up to your logic to decide if you want to push new value to the server, or pull latest from the server using Sync API.

I need to make a variable that store value of virtualPin, to compare on my device before call sync?
Another question, I use VIRTUAL_READ to get value of sensor to app, that’s work great, at the begining I alway use virtualWrite to push data to server by timer with 1s internal, than my device often disconnect, when I read again DOCS, I change to VIRTUAL_READ, but sometime I want to stop update data to server, but no way to stop VIRTUAL_READ, with virtualWrite and simpletimer, I can disable timer to stop update data to server. Anyway to stop or pause VIRTUAL_READ? or some function like APP_CONNECTED? when app connected -> do something.