摘要：
本例效果图:本例效果图:WM_NCHITTEST消息返回后,消息的Result参数表示了鼠标所在窗口的部位.窗体设计步骤:新建工程后,随便添加一个菜单;设置窗体的AutoScroll属性为True,并添加一个Panel放在合适的位置,以让窗口出现滚动条.unitUnit1;interfaceusesWindows,Messages,SysUtils,Variants,Classes,Graphics,Cont
WM_NCHITTEST 消息返回后, 消息的 Result 参数表示了鼠标所在窗口的部位.
窗体设计步骤: 新建工程后, 随便添加一个菜单; 设置窗体的 AutoScroll 属性为 True, 并添加一个 Panel 放在合适的位置, 以让窗口出现滚动条.
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, ExtCtrls, StdCtrls, Menus;
type
TForm1 = class(TForm)
Panel1: TPanel;
MainMenu1: TMainMenu;
mnuFile: TMenuItem;
private
procedure MyMsg(var msg: TWMNCHitTest); message WM_NCHITTEST;
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
const
arr: array[-2..21] of string = (
'HTERROR',
'HTTRANSPARENT',
'HTNOWHERE',
'HTCLIENT - 客户区',
'HTCAPTION - 标题',
'HTSYSMENU - 系统菜单',
'HTGROWBOX',
'HTMENU - 菜单',
'HTHSCROLL - 水平滚动条',
'HTVSCROLL - 垂直滚动条',
'HTMINBUTTON - 最小化按钮',
'HTMAXBUTTON - 最大化按钮',
'HTLEFT - 左边界',
'HTRIG - 右边界',
'HTTOP - 上边界',
'HTTOPLEFT - 左上角',
'HTTOPRIG - 右上角',
'HTBOTTOM - 下边界',
'HTBOTTOMLEFT - 左下角',
'HTBOTTOMRIG - 右下角',
'HTBORDER',
'HTOBJECT',
'HTCLOSE - 关闭按钮',
'HTHELP');
procedure TForm1.MyMsg(var msg: TWMNCHitTest);
var
i: Integer;
begin
Inherited;
i := msg.Result;
Text := Format('%d: %s', [i, arr[i]]);
end;
end.
//另附 WM_NCHITTEST 消息中 Result 参数的所有可能值的列表:
HTERROR = -2;
HTTRANSPARENT = -1;
HTNOWHERE = 0;
HTCLIENT = 1;
HTCAPTION = 2;
HTSYSMENU = 3;
HTGROWBOX = 4;
HTSIZE = HTGROWBOX;
HTMENU = 5;
HTHSCROLL = 6;
HTVSCROLL = 7;
HTMINBUTTON = 8;
HTMAXBUTTON = 9;
HTLEFT = 10;
HTRIGHT = 11;
HTTOP = 12;
HTTOPLEFT = 13;
HTTOPRIGHT = 14;
HTBOTTOM = 15;
HTBOTTOMLEFT = $10;
HTBOTTOMRIGHT = 17;
HTBORDER = 18;
HTREDUCE = HTMINBUTTON;
HTZOOM = HTMAXBUTTON;
HTSIZEFIRST = HTLEFT;
HTSIZELAST = HTBOTTOMRIGHT;
HTOBJECT = 19;
HTCLOSE = 20;
HTHELP = 21;