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Event.add<'T,'Del> Function (F#)

Event.add<'T,'Del> Function (F#)

Runs the given function each time the given event is triggered.

Namespace/Module Path: Microsoft.FSharp.Control.Event

Assembly: FSharp.Core (in FSharp.Core.dll)

// Signature:
Event.add : ('T -> unit) -> IEvent<'Del,'T> -> unit (requires delegate)

// Usage:
Event.add callback sourceEvent


Type: 'T -> unit

The function to call when the event is triggered.


Type: IEvent<'Del,'T>

The input event.

This function is named Add in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.

The following code example shows how to use the Event.add function.

let form = new Form(Text = "F# Windows Form",
                    Visible = true,
                    TopMost = true)
    |> Event.filter ( fun evArgs -> evArgs.X > 100 && evArgs.Y > 100)
    |> Event.add ( fun evArgs ->
        form.BackColor <- System.Drawing.Color.FromArgb(
            evArgs.X, evArgs.Y, evArgs.X ^^^ evArgs.Y) )

Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

© 2015 Microsoft