UIButton remove all target-actions

Swift 2:

actionButton.removeTarget(nil, action: nil, forControlEvents: .AllEvents)

Swift 3 & 4:

actionButton.removeTarget(nil, action: nil, for: .allEvents)

Objective-C:

[actionButton removeTarget: nil action: NULL forControlEvents: UIControlEventAllEvents];

Swift 3, 4, 5:

btnCancel.removeTarget(nil, action: nil, forControlEvents: UIControlEvents.AllEvents)

Call removeTarget:action:forControlEvents:, pass nil for the target, NULL for action, and use a control mask that sets all bits (UIControlEventAllEvents).

Objective-C

[someControl removeTarget:nil 
                   action:NULL 
         forControlEvents:UIControlEventAllEvents];

Swift 2

button.removeTarget(nil, action: nil, forControlEvents: .AllEvents)

Swift 3 or higher

button.removeTarget(nil, action: nil, for: .allEvents)

@progrmr's answer in Swift 2:

button.removeTarget(nil, action: nil, forControlEvents: .AllEvents)

and Swift 3:

button.removeTarget(nil, action: nil, for: .allEvents)

Note: Swift doesn't have NULL, so I tested replacing it with nil and it seems to work fine.