MOUSEINPUT structure (winuser.h)
Contains information about a simulated mouse event.
Syntax
typedef struct tagMOUSEINPUT {
LONG dx;
LONG dy;
DWORD mouseData;
DWORD dwFlags;
DWORD time;
ULONG_PTR dwExtraInfo;
} MOUSEINPUT, *PMOUSEINPUT, *LPMOUSEINPUT;
Members
dx
Type: LONG
The absolute position of the mouse, or the amount of motion since the last mouse event was generated, depending on the value of the dwFlags member. Absolute data is specified as the x coordinate of the mouse; relative data is specified as the number of pixels moved.
dy
Type: LONG
The absolute position of the mouse, or the amount of motion since the last mouse event was generated, depending on the value of the dwFlags member. Absolute data is specified as the y coordinate of the mouse; relative data is specified as the number of pixels moved.
mouseData
Type: DWORD
If dwFlags contains MOUSEEVENTF_WHEEL, then mouseData specifies the amount of wheel movement. A positive value indicates that the wheel was rotated forward, away from the user; a negative value indicates that the wheel was rotated backward, toward the user. One wheel click is defined as WHEEL_DELTA, which is 120.
Windows Vista: If dwFlags contains MOUSEEVENTF_HWHEEL, then dwData specifies the amount of wheel movement. A positive value indicates that the wheel was rotated to the right; a negative value indicates that the wheel was rotated to the left. One wheel click is defined as WHEEL_DELTA, which is 120.
If dwFlags does not contain MOUSEEVENTF_WHEEL, MOUSEEVENTF_XDOWN, or MOUSEEVENTF_XUP, then mouseData should be zero.
If dwFlags contains MOUSEEVENTF_XDOWN or MOUSEEVENTF_XUP, then mouseData specifies which X buttons were pressed or released. This value may be any combination of the following flags.
| Value | Meaning |
|---|---|
| XBUTTON1 0x0001 |
Set if the first X button is pressed or released. |
| XBUTTON2 0x0002 |
Set if the second X button is pressed or released. |
dwFlags
Type: DWORD
A set of bit flags that specify various aspects of mouse motion and button clicks. The bits in this member can be any reasonable combination of the following values.
The bit flags that specify mouse button status are set to indicate changes in status, not ongoing conditions. For example, if the left mouse button is pressed and held down, MOUSEEVENTF_LEFTDOWN is set when the left button is first pressed, but not for subsequent motions. Similarly MOUSEEVENTF_LEFTUP is set only when the button is first released.
You cannot specify both the MOUSEEVENTF_WHEEL flag and either MOUSEEVENTF_XDOWN or MOUSEEVENTF_XUP flags simultaneously in the dwFlags parameter, because they both require use of the mouseData field.
| Value | Meaning |
|---|---|
| MOUSEEVENTF_MOVE 0x0001 |
Movement occurred. |
| MOUSEEVENTF_LEFTDOWN 0x0002 |
The left button was pressed. |
| MOUSEEVENTF_LEFTUP 0x0004 |
The left button was released. |
| MOUSEEVENTF_RIGHTDOWN 0x0008 |
The right button was pressed. |
| MOUSEEVENTF_RIGHTUP 0x0010 |
The right button was released. |
| MOUSEEVENTF_MIDDLEDOWN 0x0020 |
The middle button was pressed. |
| MOUSEEVENTF_MIDDLEUP 0x0040 |
The middle button was released. |
| MOUSEEVENTF_XDOWN 0x0080 |
An X button was pressed. |
| MOUSEEVENTF_XUP 0x0100 |
An X button was released. |
| MOUSEEVENTF_WHEEL 0x0800 |
The wheel was moved, if the mouse has a wheel. The amount of movement is specified in mouseData. |
| MOUSEEVENTF_HWHEEL 0x1000 |
The wheel was moved horizontally, if the mouse has a wheel. The amount of movement is specified in mouseData. Windows XP/2000: This value is not supported. |
| MOUSEEVENTF_MOVE_NOCOALESCE 0x2000 |
The WM_MOUSEMOVE messages will not be coalesced. The default behavior is to coalesce WM_MOUSEMOVE messages. Windows XP/2000: This value is not supported. |
| MOUSEEVENTF_VIRTUALDESK 0x4000 |
Maps coordinates to the entire desktop. Must be used with MOUSEEVENTF_ABSOLUTE. |
| MOUSEEVENTF_ABSOLUTE 0x8000 |
The dx and dy members contain normalized absolute coordinates. If the flag is not set, dxand dy contain relative data (the change in position since the last reported position). This flag can be set, or not set, regardless of what kind of mouse or other pointing device, if any, is connected to the system. For further information about relative mouse motion, see the following Remarks section. |
time
Type: DWORD
The time stamp for the event, in milliseconds. If this parameter is 0, the system will provide its own time stamp.
dwExtraInfo
Type: ULONG_PTR
An additional value associated with the mouse event. An application calls GetMessageExtraInfo to obtain this extra information.
Remarks
If the mouse has moved, indicated by MOUSEEVENTF_MOVE, dx and dy specify information about that movement. The information is specified as absolute or relative integer values.
If MOUSEEVENTF_ABSOLUTE value is specified, dx and dy contain normalized absolute coordinates between 0 and 65,535. The event procedure maps these coordinates onto the display surface. Coordinate (0,0) maps onto the upper-left corner of the display surface; coordinate (65535,65535) maps onto the lower-right corner. In a multimonitor system, the coordinates map to the primary monitor.
If MOUSEEVENTF_VIRTUALDESK is specified, the coordinates map to the entire virtual desktop.
If the MOUSEEVENTF_ABSOLUTE value is not specified, dxand dy specify movement relative to the previous mouse event (the last reported position). Positive values mean the mouse moved right (or down); negative values mean the mouse moved left (or up).
Relative mouse motion is subject to the effects of the mouse speed and the two-mouse threshold values. A user sets these three values with the Pointer Speed slider of the Control Panel's Mouse Properties sheet. You can obtain and set these values using the SystemParametersInfo function.
The system applies two tests to the specified relative mouse movement. If the specified distance along either the x or y axis is greater than the first mouse threshold value, and the mouse speed is not zero, the system doubles the distance. If the specified distance along either the x or y axis is greater than the second mouse threshold value, and the mouse speed is equal to two, the system doubles the distance that resulted from applying the first threshold test. It is thus possible for the system to multiply specified relative mouse movement along the x or y axis by up to four times.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Header | winuser.h (include Windows.h) |
See also
Conceptual
Reference
Feedback
Coming soon: Throughout 2024 we will be phasing out GitHub Issues as the feedback mechanism for content and replacing it with a new feedback system. For more information see: https://aka.ms/ContentUserFeedback.
Submit and view feedback for