My.Computer.Mouse.WheelScrollLines Property 

Gets a number that indicates how much to scroll when the mouse wheel is rotated one notch.

' Usage
Dim value As Integer = My.Computer.Mouse.WheelScrollLines
' Declaration
Public ReadOnly Property WheelScrollLines As Integer

Return Value

An Integer that indicates how much to scroll when the mouse wheel is rotated one notch. A positive value indicates scrolling by that number of lines, while a negative value indicates scrolling by one screen at a time.

Exceptions

The following conditions can cause an exception:

• The computer has no mouse installed (InvalidOperationException).

• The mouse has no scroll wheel (InvalidOperationException).

Remarks

You can use this property to determine how many lines to scroll up or down in a multi-line control that has a scroll bar.

The My.Computer.Mouse.WheelScrollLines property provides functionality similar to the MouseWheelScrollLines property.

Because this property throws an exception if the mouse does not have a scroll wheel, you should make sure a mouse has a scroll wheel by checking the My.Computer.Mouse.WheelExists property.

This property provides information about the computer that runs the code.

Example

This example determines if the mouse has a scroll wheel and uses the My.Computer.Mouse.WheelExists property to determine how much to scroll when the mouse wheel is rotated.

If My.Computer.Mouse.WheelExists Then
    Dim lines As Integer = My.Computer.Mouse.WheelScrollLines
    If lines > 0 Then
        MsgBox("Application scrolls " & _
            lines & " line(s) for each wheel turn.")
    Else
        MsgBox("Application scrolls " & _
            (-lines) & " page(s) for each wheel turn.")
    End If
Else
    MsgBox("Mouse has no scroll wheel.")
End If

Requirements

Namespace: Microsoft.VisualBasic.Devices

Class: Mouse

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

Availability by Project Type

Permissions

No permissions are required.

See Also

Reference

My.Computer.Mouse Object
My.Computer.Mouse.WheelExists Property
Microsoft.VisualBasic.Devices.Mouse.WheelScrollLines