Assembly: Microsoft.Xna.Framework (in microsoft.xna.framework.dll)
For digital buttons (such as A, START, and right bumper) the return value indicates whether the button is pressed.
For analog inputs (triggers and thumbsticks), the return value indicates whether the input exceeds dead zone values. For example, a trigger will not be reported as pressed until it is pulled about 12% of its full range. IsButtonDown always uses the default dead zone processing mode, GamePadDeadZone.IndependentAxes.
If multiple buttons are specified (by combining them using the bitwise OR operator), then all must be pressed (or exceed dead zone values) in order for IsButtonDown to return true.