"Write to text file" when button is pushed?

[Johan.svensson]

I want to use the function "write to text file" when a button is pushed, and write only once.

The same goes for "read from text file

[Dennis_Knutson]

All you need to do is use an event structure and put the functions inside the value change event. Set the mechanical action of the Booleans to latch. If you don't have the event structure, put them inside a case statement.

[Jimmie_A.]

Hello!

Look at the following examples shipped with LabVIEW Professional and LabVIEW Full. Event structure example is not installed with Base package. 

Open up 'Example Finder', click on the 'Search' tab, enter keyword 'events' and you fill find several examples. The ones of interest for you is 'New Event Handler.VI" and 'Old Event Handler.VI', where the first uses the event structure and the other uses the standard state machine architecture.