Direction

There are four directions in which a property can point:

• In: The most common. Used for input arguments.
• Out: Used for output arguments, the results of an activity.
• InOut: Rarely used, but can be handy in activities that take in data, modify it, and output it for use in other activities.

• None: Discrete types like Booleans and Enums do not require a direction. Use None when creating properties of these types.

  Note: Note that Out and InOut properties can only accept variables, not literal values, in UiPath Studio. This makes sense since the activity needs something to which the outputted value can be written.

Generated Code

The Argument direction is seen in the declaration of each property. Notice that FirstNumber and SecondNumber are both InArguments while Sum is an OutArgument.

...
#region Properties
[LocalizedDisplayName(nameof(Resources.Addition_FirstNumber_DisplayName))]
[LocalizedDescription(nameof(Resources.Addition_FirstNumber_Description))]
[LocalizedCategory(nameof(Resources.Input_Category))]
public InArgument<int> FirstNumber { get; set; }
[LocalizedDisplayName(nameof(Resources.Addition_SecondNumber_DisplayName))]
[LocalizedDescription(nameof(Resources.Addition_SecondNumber_Description))]
[LocalizedCategory(nameof(Resources.Input_Category))]
public InArgument<int> SecondNumber { get; set; }
[LocalizedDisplayName(nameof(Resources.Addition_Sum_DisplayName))]
[LocalizedDescription(nameof(Resources.Addition_Sum_Description))]
[LocalizedCategory(nameof(Resources.Output_Category))]
public OutArgument<int> Sum { get; set; }
#endregion
...

Effect in UiPath Studio

Hover over each property in the Properties Pane to see its direction.