Create local variables for front panel objects in a single VI when you do not have access to a front panel object or you need to pass data between block diagram nodes. When you create a local variable, it appears on the block diagram, but it does not appear on the front panel.

With a local variable, you can write to or read from a control or indicator on the front panel. Writing to a local variable is similar to passing data to any other terminal. However, with a local variable you can write to it even if it is a control or read from it even if it is an indicator. In effect, with a local variable, you can access a front panel object as both an input and an output.

For example, if the user interface requires users to log in, you can clear the Login and Password prompts each time a new user logs in. Use a local variable to read from the Login and Password string controls when a user logs in and to write empty strings to these controls when the user logs out.