SendInput Function

Declare Function SendInput Lib "user32.dll" (ByVal nInputs As Long, pInputs As INPUT_TYPE, ByVal cbSize As Long) As Long

Platforms

Windows 95: Not Supported.
Windows 98: Supported.
Windows NT: Requires Windows NT 4.0 with Service Pack 3 (SP3) or later.
Windows 2000: Supported.
Windows CE: Requires Windows CE 2.0 or later.

Description & Usage

SendInput synthesizes a series of keyboard, mouse, or other hardware inputs and adds them the input stream. The events generated by the function are not intersperced with any other input messages, user-created or otherwise.

Return Value

If an error occured, the function returns 0 (use GetLastError to get the error code). If successful, the function returns the number of input events which were successfully added to the input stream.

Visual Basic-Specific Issues

None.

Parameters

nInputs: The number of elements in the array passed as pInputs.
pInputs: An array holding information about each input event to insert into the input stream. Each element corresponds to a single input event.
cbSize: The size in bytes of a single INPUT_TYPE structure (not the total size of the array passed as pInputs.

Example

' Synthesize the user typing the letter P followed by clicking
' the right mouse button.  Note how the information for each individual input
' event is placed in its associated structure before copying it into the
' input array.
Dim inputevents(0 To 3) As INPUT_TYPE  ' holds information about each event
Dim keyevent As KEYBDINPUT  ' temporarily hold keyboard input info
Dim mouseevent As MOUSEINPUT  ' temporarily hold mouse input info

' Load the information needed to synthesize pressing the P key.
keyevent.wVk = VK_P  ' the P key
keyevent.wScan = 0  ' not needed
keyevent.dwFlags = 0  ' press the key down
keyevent.time = 0  ' use the default
keyevent.dwExtraInfo = 0  ' not needed
' Copy the structure into the input array's buffer.
inputevents(0).dwType = INPUT_KEYBOARD  ' keyboard input
CopyMemory inputevents(0).xi(0), keyevent, Len(keyevent)

' Do the same as above, but for releasing the P key.
keyevent.wVk = VK_P  ' the P key
keyevent.wScan = 0  ' not needed
keyevent.dwFlags = KEYEVENTF_KEYUP  ' release the key
keyevent.time = 0  ' use the default
keyevent.dwExtraInfo = 0  ' not needed
inputevents(1).dwType = INPUT_KEYBOARD  ' keyboard input
CopyMemory inputevents(1).xi(0), keyevent, Len(keyevent)

' Load the information needed to synthesize pressing the right mouse button.
mouseevent.dx = 0  ' no horizontal movement
mouseevent.dy = 0  ' no vertical movement
mouseevent.mouseData = 0  ' not needed
mouseevent.dwFlags = MOUSEEVENTF_RIGHTDOWN  ' right button down
mouseevent.dwTime = 0  ' use the default
mouseevent.dwExtraInfo = 0  ' not needed
' Copy the structure into the input array's buffer.
inputarray(2).dwType = INPUT_MOUSE  ' mouse input
CopyMemory inputevents(2).xi(0), mouseevent, Len(mouseevent)

' Do the same as above, but for releasing the right mouse button.
mouseevent.dx = 0  ' no horizontal movement
mouseevent.dy = 0  ' no vertical movement
mouseevent.mouseData = 0  ' not needed
mouseevent.dwFlags = MOUSEEVENTF_RIGHTUP  ' right button up
mouseevent.dwTime = 0  ' use the default
mouseevent.dwExtraInfo = 0  ' not needed
' Copy the structure into the input array's buffer.
inputarray(3).dwType = INPUT_MOUSE  ' mouse input
CopyMemory inputevents(3).xi(0), mouseevent, Len(mouseevent)

' Now that all the information for the four input events has been placed
' into the array, finally send it into the input stream.
SendInput(4, inputarray(0), Len(inputarray(0))  ' place the events into the stream

Related Functions

keybd_event, mouse_event