{
标题：基于数据库的动态菜单
说明：
通过数据表信息来动态创建菜单(此段代码主要起到抛砖引玉.菜单的数据的读取略显拙劣有待于改进.同志们可以讨论优化此段代码)。
目前笔者正在做业务基础平台的开发，有那伟仁兄有好的想法意见欢迎互相学习沟通！
作者：ABCDE(李克俭)
日期：2006-11-22
QQ：39839655
EMAIL：JulyXDay@QQ.COM
数据结构：
CREATE TABLE [dbo].[SysMenu](
[Id] [int] IDENTITY(1,1) NOT NULL,
[Name] [varchar](20) COLLATE Chinese_PRC_CI_AS NULL,
[Title] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL,
[ImgIdx] [int] NULL CONSTRAINT [DF_SysMenu_ImgIndex] DEFAULT ((-1)),
[ShortCut] [int] NULL CONSTRAINT [DF_SysMenu_ShortCut] DEFAULT ((-1)),
[OperMode] [int] NULL CONSTRAINT [DF_SysMenu_OperMode] DEFAULT ((-1)), --操作模式：-1.无操作; 1.打开窗体; 2.运行通用查询; 3.运行脚本; 4.调用系统过程
[OperContext] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL, --根据不同操作模式,来编写不同操作文本,可以是：窗体的类名,通用查询标示,脚本,系统中一个过程的名称(TNotifyEvent = procedure(Sender: TObject) of object;)
[PermId] [int] NULL CONSTRAINT [DF_SysMenu_PermId] DEFAULT ((-1)),
[ParentId] [int] NULL CONSTRAINT [DF_SysMenu_ParentId] DEFAULT ((-1)),
[Priority] [int] NULL CONSTRAINT [DF_SysMenu_Priority] DEFAULT ((0)),
[CreateDate] [datetime] NULL CONSTRAINT [DF_SysMenu_CreateDate] DEFAULT (getdate()),
[EditDate] [datetime] NULL,
[State] [int] NULL CONSTRAINT [DF_SysMenu_State] DEFAULT ((0)),
CONSTRAINT [PK_SysMenu] PRIMARY KEY CLUSTERED
(
[Id] ASC
)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]
}
//---------- 结构体、常量的声明部分 ----------
ShortCuts: array[0..108] of TShortCut = (
scNone,
Byte('A') or scCtrl,
Byte('B') or scCtrl,
Byte('C') or scCtrl,
Byte('D') or scCtrl,
Byte('E') or scCtrl,
Byte('F') or scCtrl,
Byte('G') or scCtrl,
Byte('H') or scCtrl,
Byte('I') or scCtrl,
Byte('J') or scCtrl,
Byte('K') or scCtrl,
Byte('L') or scCtrl,
Byte('M') or scCtrl,
Byte('N') or scCtrl,
Byte('O') or scCtrl,
Byte('P') or scCtrl,
Byte('Q') or scCtrl,
Byte('R') or scCtrl,
Byte('S') or scCtrl,
Byte('T') or scCtrl,
Byte('U') or scCtrl,
Byte('V') or scCtrl,
Byte('W') or scCtrl,
Byte('X') or scCtrl,
Byte('Y') or scCtrl,
Byte('Z') or scCtrl,
Byte('A') or scCtrl or scAlt,
Byte('B') or scCtrl or scAlt,
Byte('C') or scCtrl or scAlt,
Byte('D') or scCtrl or scAlt,
Byte('E') or scCtrl or scAlt,
Byte('F') or scCtrl or scAlt,
Byte('G') or scCtrl or scAlt,
Byte('H') or scCtrl or scAlt,
Byte('I') or scCtrl or scAlt,
Byte('J') or scCtrl or scAlt,
Byte('K') or scCtrl or scAlt,
Byte('L') or scCtrl or scAlt,
Byte('M') or scCtrl or scAlt,
Byte('N') or scCtrl or scAlt,
Byte('O') or scCtrl or scAlt,
Byte('P') or scCtrl or scAlt,
Byte('Q') or scCtrl or scAlt,
Byte('R') or scCtrl or scAlt,
Byte('S') or scCtrl or scAlt,
Byte('T') or scCtrl or scAlt,
Byte('U') or scCtrl or scAlt,
Byte('V') or scCtrl or scAlt,
Byte('W') or scCtrl or scAlt,
Byte('X') or scCtrl or scAlt,
Byte('Y') or scCtrl or scAlt,
Byte('Z') or scCtrl or scAlt,
VK_F1,
VK_F2,
VK_F3,
VK_F4,
VK_F5,
VK_F6,
VK_F7,
VK_F8,
VK_F9,
VK_F10,
VK_F11,
VK_F12,
VK_F1 or scCtrl,
VK_F2 or scCtrl,
VK_F3 or scCtrl,
VK_F4 or scCtrl,
VK_F5 or scCtrl,
VK_F6 or scCtrl,
VK_F7 or scCtrl,
VK_F8 or scCtrl,
VK_F9 or scCtrl,
VK_F10 or scCtrl,
VK_F11 or scCtrl,
VK_F12 or scCtrl,
VK_F1 or scShift,
VK_F2 or scShift,
VK_F3 or scShift,
VK_F4 or scShift,
VK_F5 or scShift,
VK_F6 or scShift,
VK_F7 or scShift,
VK_F8 or scShift,
VK_F9 or scShift,
VK_F10 or scShift,
VK_F11 or scShift,
VK_F12 or scShift,
VK_F1 or scShift or scCtrl,
VK_F2 or scShift or scCtrl,
VK_F3 or scShift or scCtrl,
VK_F4 or scShift or scCtrl,
VK_F5 or scShift or scCtrl,
VK_F6 or scShift or scCtrl,
VK_F7 or scShift or scCtrl,
VK_F8 or scShift or scCtrl,
VK_F9 or scShift or scCtrl,
VK_F10 or scShift or scCtrl,
VK_F11 or scShift or scCtrl,
VK_F12 or scShift or scCtrl,
VK_INSERT,
VK_INSERT or scShift,
VK_INSERT or scCtrl,
VK_DELETE,
VK_DELETE or scShift,
VK_DELETE or scCtrl,
VK_BACK or scAlt,
VK_BACK or scShift or scAlt);
type
PMenuData = ^TMenuData;
TMenuData = record
Id: Integer;
Name: string;
OperMode: Integer;
OperContext: string;
PermId: Integer;
ShortCut: TShortCut;
end;
//---------- TMenuItemEx 类的声明部分 ----------
type
TMenuItemEx = class(TMenuItem)
private
{ Private declarations }
protected
{ Protected declarations }
public
{ Public declarations }
Data: Pointer;
published
{ Published declarations }
end;
//---------- 相关函数的声明 ----------
function GetSingleValue(ACon: TADOConnection; ASQL: string; AFieldName: string=''): string;
var
fTmp: Fields;
begin
Result := '';
fTmp := GetSingleRow(ACon, ASQL);
if not Assigned(fTmp) then Exit;
if AFieldName = '' then
Result := VarToStr(fTmp[0].Value)
else
Result := VarToStr(fTmp[AFieldName].Value);
end;
//---------- 动态菜单实现部分----------
//mmMain 为窗体上的菜单控件...
procedure TMainFrm.CreateSysMenu(AMenuId: Integer; AMenuItem: TMenuItem);
var
i: Integer;
oRs: _Recordset;
oMenuItem: TMenuItemEx;
pMenuDataA: PMenuData;
MenuItemMethod: TMethod;
begin
oRs := FrmData.conMain.Execute('SELECT * FROM SysMenu WHERE ParentId=' + IntToStr(AMenuId) + ' ORDER BY Priority');
for i := 0 to oRs.RecordCount - 1 do
begin
New(pMenuDataA);
pMenuDataA^.Id := oRs.Fields['Id'].Value;
pMenuDataA^.Name := VarToStr(oRs.Fields['Name'].Value);
pMenuDataA^.OperMode := oRs.Fields['OperMode'].Value;
pMenuDataA^.OperContext := VarToStr(oRs.Fields['OperContext'].Value);
pMenuDataA^.PermId := oRs.Fields['PermId'].Value;
pMenuDataA^.ShortCut := oRs.Fields['ShortCut'].Value;
oMenuItem := TMenuItemEx.Create(mmMain);
oMenuItem.Caption := VarToStr(oRs.Fields['Title'].Value);
oMenuItem.ImageIndex := oRs.Fields['ImgIdx'].Value;
oMenuItem.ShortCut := oRs.Fields['ShortCut'].Value;
if pMenuDataA^.PermId <> -1 then
oMenuItem.Visible := ck(pMenuDataA^.PermId);
oMenuItem.Enabled := oMenuItem.Visible;
oMenuItem.Data := pMenuDataA;
if pMenuDataA^.OperMode <> -1 then
oMenuItem.OnClick := AMenuItemClick;
if (pMenuDataA^.OperMode = 3) and (Assigned(Self.MethodAddress(pMenuDataA^.OperContext))) then
begin
MenuItemMethod.Code := Self.MethodAddress(pMenuDataA^.OperContext);
MenuItemMethod.Data := oMenuItem;
oMenuItem.OnClick := TNotifyEvent(MenuItemMethod);
end;
if not Assigned(AMenuItem) then
mmMain.Items.Add(oMenuItem)
else
AMenuItem.Add(oMenuItem);
if StrToIntDef(GetSingleValue(FrmData.conMain, 'SELECT COUNT(*) FROM SysMenu WHERE ParentId=' + IntToStr(AMenuId)), 0) > 0 then
CreateSysMenu(oRs.Fields['Id'].Value, oMenuItem);
oRs.MoveNext;
end;
end;
function TMainFrm.AdjustMenuSplit(AMenuItem: TMenuItem): Boolean;
function IsSubItemVisible(BMenuItem: TMenuItem): Boolean;
var
j: Integer;
begin
Result := False;
for j := 0 to BMenuItem.Count - 1 do
if (BMenuItem.Items[j].Caption <> '-') and (BMenuItem.Items[j].Visible) then
Result := True;
end;
var
i: Integer;
IsPrevSplit: Boolean;
begin
Result := False;
if AMenuItem = nil then
AMenuItem := mmMain.Items;
IsPrevSplit := True;
for i := 0 to AMenuItem.Count -1 do
begin
if AMenuItem.Items[i].Count > 0 then
begin
if (AMenuItem.Items[i].Visible) and (not IsSubItemVisible(AMenuItem.Items[i])) then
Result := True;
AMenuItem.Items[i].Visible := IsSubItemVisible(AMenuItem.Items[i]);
AdjustMenuSplit(AMenuItem.Items[i]);
end;
if AMenuItem.Items[i].Visible then
if AMenuItem.Items[i].Caption = '-' then
begin
if IsPrevSplit then
AMenuItem.Items[i].Visible := False;
IsPrevSplit := True;
end
else
IsPrevSplit := False;
end;
end;
procedure TMainFrm.AdjustMenuSplit_(AMenuItem: TMenuItem);
function GetNextVisbleItem(CMenuItem: TMenuItem; AItemIndex: Integer) :TMenuItem;
var
k: Integer;
begin
Result := nil;
for k := AItemIndex to CMenuItem.Count - 1 do
if CMenuItem.Items[k].Visible then
begin
Result := CMenuItem.Items[k];
Exit;
end;
end;
var
i: Integer;
NextVisbleItem: TMenuItem;
begin
if AMenuItem = nil then
AMenuItem := mmMain.Items;
for i := 0 to AMenuItem.Count -1 do
begin
if AMenuItem.Items[i].Count > 0 then
AdjustMenuSplit_(AMenuItem.Items[i]);
if (AMenuItem.Items[i].Visible) and (AMenuItem.Items[i].Caption = '-') then
begin
NextVisbleItem := GetNextVisbleItem(AMenuItem, i + 1);
if Assigned(NextVisbleItem) then
AMenuItem.Items[i].Visible := not (NextVisbleItem.Caption = '-')
else
AMenuItem.Items[i].Visible := False;
end;
end;
end;
procedure TMainFrm.InitiSysMenu;
begin
mmMain.Items.Clear;
CreateSysMenu;
while AdjustMenuSplit do
AdjustMenuSplit_;
end;
procedure TMainFrm.AMenuItemClick(Sender: TObject);
var
pMenuDataA: PMenuData;
begin
if (Assigned(Sender)) and (Sender is TMenuItemEx) then
begin
pMenuDataA := TMenuItemEx(Sender).Data;
case pMenuDataA^.OperMode of
0: OpenFrm(pMenuDataA^.OperContext);
1: OpenQry(pMenuDataA^.OperContext);
2: ExecScript(pMenuDataA^.OperContext);
end;
end;
end;
procedure TMainFrm.OpenFrm(AFrmClsName: string);
var
clsFrm: TFormClass;
oFrm: TForm;
begin
clsFrm := TFormClass(GetClass(AFrmClsName));
if Assigned(clsFrm) then
begin
if not FrmExist(AFrmClsName) then
begin
oFrm := clsFrm.Create(Self);
oFrm.Show;
end;
end
else
raise Exception.Create('无法打开窗体，窗体类 ' + AFrmClsName + ' 没有注册。');
end;
procedure TMainFrm.OpenQry(AQryName: string);
var
ofrmQry: TfrmPubQry;
begin
ofrmQry := TfrmPubQry.Create(Self, AQryName);
ofrmQry.Show;
end;
procedure TMainFrm.ExecCustomMethod(AMethod: string; Sender: TObject);
begin
//
end;
procedure TMainFrm.ExecScript(AScript: string);
begin
//可以使用常规的 Script 引擎来实现比如 FastScript .....
end; |
