All templates
Flow ControlIntermediate

Use Subflows to Check if File Exists

Robomotion•Updated 6 months ago
Use Subflows to Check if File Exists

Overview

Encapsulates a "does this file exist?" check inside a reusable subflow so the main flow stays linear and readable.

Use Subflows to Check if File Exists

Automating complex scenarios may lead to large flows with recurrent nodes. Subflows are reusable groups of nodes that split flows, making them more manageable and easier to maintain.

What Use Subflows to Check if File Exists can do

  • Input Dialog titled Check if file exists, message Please populate a file name to check if it exists in your desktop folder., default FileName -> msg.user_input.
  • Branch on cancel (Core.Programming.Function, outputs: 2) — empty input short-circuits to Core.Flow.Stop.
  • Build path (Core.Programming.Function) — msg.candidate_path = global.get('$Home$') + '\Desktop\' + msg.user_input.
  • Core.FileSystem.PathExists on msg.candidate_path -> msg.exists.
  • Branch on existence (Core.Programming.Function, outputs: 2) — routes to Core.Flow.SubFlow Call File_Exists or Call File_Does_Not_Exist.

Behind the scenes

  • The teaching point is subflow routing: instead of an IF/ELSE with inline nodes, route to two differently-named subflows. Keep each subflow minimal — they show the difference from the label and IF-based versions of this tutorial.
  • msg.* fields (user_input, candidate_path, exists) ride the message across the Core.Flow.SubFlow call, so the child flows can read them without any extra wiring.