Using the hook function [3]

A two-step:

First, establish the DLL, and implement the hook in the DLL settings, release and hook function;

Second, build another project call test.

The first step: do the DLL

First build a DLL project, the initial code is as follows (remove the annotation):

Library Project1

uses
Sysutils,
Classes;

{$R *.res}

Begin
End.


//Save the project as MYHOOK.DPR and implement the following:

Library Myhook

uses
Sysutils,
windows, {Hook functions from Windows Unit}
Messages, {message wm_lbuttondown defined in Messages cell}
classes;
{$R *.res}

var
hook:hhook; {Hook variable}

{hook function, mouse message too much (for example, mouse movement), must have a choice, here Select the left mouse button press}
function Mousehook (ncode:integer; wparam:wparam; Lparam:lpara　M): lresult; stdcall;
Begin
If WParam = Wm_lbuttondown then
begin
MessageBeep (0),
end;
Result: = CallNextHookEx (Hook, ncode, WParam, LParam);
End;

{Create hook}
function Sethook:boolean stdcall
begin
Hook: = SetWindowsHookEx (Wh_mouse, @MouseHook, HIns tance, 0);
Result: = Hook <> 0;
End;

{release Hook}
function Delhook:boolean stdcall
Begin
Result: = UnhookWindowsHookEx (hook);
End;
br> {output function as required by DLL}
Exports
Sethook name 'Sethook ',
Delhook name ' Delhook ',
Mousehook name ' Mousehook ';
　
//sethook, Delhook, Mousehook; {If you do not need to change your name, you can exports it directly}

Begin
End.

Note: The first parameter of SetWindowsHookEx wh_mouse that this is a mouse hook; The fourth parameter 0 illustrates the global.

The mouse hook callback function is formatted here: www.cnblogs.com/del/archive/2008/02/25/1080724.html

Then press CTRL+F9 to compile, in the engineering directory will generate a file with the same name as the project, here is: MyHook.dll.