delphi的BPL应用

本文主要是介绍delphi的BPL应用，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

最近一直在测试BPL和DLL，总结一下这段时间的经验。
如果是模块化架构，就选择BPL，不要选择DLL，DLL可以对外做接口使用，不过Delphi接口我觉得DataSnap更方便点。为什么要用BPL呢，因为DLL是无法传递对象的，只能传递对象的内存地址过去。BPL就可以实现对象的传递。
使用BPL的注意事项，首先一定要注意Debug 和Release 两种编译是有很大区别的。直接Release编译最好，主程序也要用Release编译调用，如果编译类型不同，会有异常提示。BPL里面各个Form和Unit之间的调用，需要注意的如果用到了Form的控件，记得一定要把Form对象传过去。这样获取才不会出问题。BPL调用BPL的时候，也要把Form传过去，传回来的时候再转换回来。下面说下调用案例。
我是一个主程序，两个BPL
主程序调用的代码

procedure TFMenuItem.Label1DblClick(Sender: TObject);
varBPLHandle: HMODULE;frm: TCustomForm;AClass : TPersistentClass;SetUser:procedure(sform:TForm;User:String;IP:String;Port:Integer);newPage:TAdvTabSheet;Path:String;ClassName:String;SetName:String;
begin//BPL的目录和名称Path:='System/'+Copy(self.Caption,1,2)+'.bpl';//调用的Form的名称ClassName:='T'+self.Caption;//BPL里面的过程名称SetName:=self.Caption+'SetUser';//加载BPLBPLHandle := LoadPackage(Path);//加载后获取过程@SetUser := GetProcAddress(BPLHandle, Pchar(SetName));if BPLHandle > 0 thenbegin//获取FormAClass := FindClass(ClassName);if AClass<>nil thenbegin//新增一个Page页面newPage:=TAdvTabSheet.Create(FMyMain.AdvPageControl2);newPage.Caption:=Label1.Caption;newPage.Color:=clWhite;newPage.AdvPageControl:=FMyMain.AdvPageControl2;newPage.ShowClose:=True;FMyMain.AdvPageControl2.ActivePage:=newPage;//创建BPL的Form实例frm:=TComponentClass(AClass).Create(Application) as TCustomForm;if @SetUser<>nil then//执行BPL里面的过程SetUser(TForm(frm),'admin',FMyMain.DSRestConnection1.Host,FMyMain.DSRestConnection1.Port);//放入新建的Page里面frm.Parent:=newPage;//显示frm.Show;// frm.Free;endend
end;

第一个BPL的代码

unit User;interfaceusesWinapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,System.Classes, Vcl.Graphics,Vcl.Controls, Vcl.Forms, Vcl.Dialogs, DBGridEhGrouping, ToolCtrlsEh,DBGridEhToolCtrls, DynVarsEh, FireDAC.Stan.Intf, FireDAC.Stan.Option,FireDAC.Stan.Param, FireDAC.Stan.Error, FireDAC.DatS, FireDAC.Phys.Intf,FireDAC.DApt.Intf, Vcl.ComCtrls, Vcl.ToolWin, System.ImageList, Vcl.ImgList,Data.DB, FireDAC.Comp.DataSet, FireDAC.Comp.Client, EhLibVCL, GridsEh,DBAxisGridsEh, DBGridEh, AdvEdit, AdvEdBtn, Vcl.StdCtrls, Vcl.ExtCtrls,Datasnap.DSClientRest, FireDAC.Stan.StorageJSON,FireDAC.Stan.StorageXML, FireDAC.Stan.StorageBin,DataBase;type//定义回调过程MeADD=procedure(DepCode:String;DepName:String;MyForm:TForm);TF901 = class(TForm)Panel1: TPanel;Label1: TLabel;Label2: TLabel;Label3: TLabel;Label4: TLabel;Label5: TLabel;Label6: TLabel;Edit1: TEdit;Edit2: TEdit;Edit3: TEdit;Edit4: TEdit;Edit5: TEdit;Edit7: TEdit;Edit6: TAdvEditBtn;Panel2: TPanel;DBGridEh1: TDBGridEh;Panel3: TPanel;DataSource1: TDataSource;FDMemTable1: TFDMemTable;ImageList1: TImageList;ToolBar1: TToolBar;ToolButton1: TToolButton;ToolButton2: TToolButton;ToolButton3: TToolButton;ToolButton4: TToolButton;ToolButton10: TToolButton;ToolButton5: TToolButton;ToolButton6: TToolButton;ToolButton7: TToolButton;ToolButton8: TToolButton;procedure ToolButton1Click(Sender: TObject);procedure ToolButton2Click(Sender: TObject);procedure ToolButton3Click(Sender: TObject);procedure ToolButton4Click(Sender: TObject);procedure ToolButton10Click(Sender: TObject);procedure FormShow(Sender: TObject);procedure ToolButton8Click(Sender: TObject);procedure Edit6ClickBtn(Sender: TObject);private{ Private declarations }public{ Public declarations }varUserNo:String;MyDataBase:TDDataBase;end;//定义给主程序调用的过程procedure F901SetUser(sform:TForm;UserNo:String;IP:String;Port:Integer);//定义一个跟回调过程一样的过程，这个用于回调过程功能实现procedure SetDep(depcode:String;depname:String;MyForm:TForm);
varF901: TF901;implementation
Uses DataPost;
{$R *.dfm}//给主程序调用的过程
procedure F901SetUser(sform:TForm;UserNo:String;IP:String;Port:Integer);
beginTF901(sform).UserNo:=UserNo;TF901(sform).MyDataBase:=DataPost.ConnectData(IP,Port);
end;//一个跟回调过程一样的过程，这个用于回调过程功能实现
procedure SetDep(depcode:String;depname:String;MyForm:TForm);
beginTF901(MyForm).Edit7.Text:=depcode;TF901(MyForm).Edit6.Text:=depname;
end;//BPL里面调用另外一个BPL
procedure TF901.Edit6ClickBtn(Sender: TObject);
varBPLHandle: HMODULE;frm: TCustomForm;AClass : TPersistentClass;DepSetUser:procedure(sform:TForm;tForm:TForm;User:String;IP:String;Port:Integer);PMeADD:procedure(me:MeADD);
begin//加载BPLBPLHandle := LoadPackage('Share/DepBPL.bpl');//这里跟主程序调用的一样，调用另外一个BPL的过程@DepSetUser := GetProcAddress(BPLHandle, 'DepSetUser');//另外一个BPL回调本BPL的过程@PMeADD := GetProcAddress(BPLHandle, 'PMeADD');if BPLHandle > 0 thenbegin//获取FormAClass := FindClass('TFQueryDep');if AClass<>nil thenbegin//创建另外一个BPL的Form实例frm:=TComponentClass(AClass).Create(Application) as TCustomForm;if @DepSetUser<>nil then//调用里面的过程 DepSetUser(TForm(frm),self,'admin',MyDataBase.DSRestConnection1.Host,MyDataBase.DSRestConnection1.Port);if @PMeADD<>nil then//把实现回调功能的过程传过去PMeADD(SetDep);frm.ShowModal;frm.Free;endendend;procedure TF901.FormShow(Sender: TObject);
beginDataPost.ButtonPower(Self.Name,self.UserNo,self.ToolBar1,self.MyDataBase);DataPost.F901OpenData(self);
end;procedure TF901.ToolButton10Click(Sender: TObject);
beginDataPost.F901Cancel(self);
end;procedure TF901.ToolButton1Click(Sender: TObject);
beginDataPost.F901Add(self);
end;procedure TF901.ToolButton2Click(Sender: TObject);
beginDataPost.F901Update(self);
end;procedure TF901.ToolButton3Click(Sender: TObject);
beginDataPost.F901Delete(self);end;procedure TF901.ToolButton4Click(Sender: TObject);
beginDataPost.F901Save(self);
end;procedure TF901.ToolButton8Click(Sender: TObject);
beginDataPost.F901Cancel(self);
end;//这里是给主程序显示可调用的过程
exportsF901SetUser;//这里把Form给主程序定位Form使用
initializationRegisterClass(TF901);
finalizationUnRegisterClass(TF901);end.

第二个BPL代码

unit QueryDep;interfaceusesWinapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,Vcl.Controls, Vcl.Forms, Vcl.Dialogs, DBGridEhGrouping, ToolCtrlsEh,DBGridEhToolCtrls, DynVarsEh, EhLibVCL, GridsEh, DBAxisGridsEh, DBGridEh,FireDAC.Stan.Intf, FireDAC.Stan.Option, FireDAC.Stan.Param,FireDAC.Stan.Error, FireDAC.DatS, FireDAC.Phys.Intf, FireDAC.DApt.Intf,FireDAC.Stan.Async, FireDAC.DApt, Data.DB, FireDAC.Comp.DataSet,FireDAC.Comp.Client, Vcl.StdCtrls, Vcl.ExtCtrls, Vcl.Imaging.pngimage,Vcl.ShadowForms,Datasnap.DSClientRest,system.IniFiles,Data.FireDACJSONReflect,FireDAC.Stan.StorageXML, FireDAC.Stan.StorageJSON, FireDAC.Stan.StorageBin;type//定义回调过程MeADD=procedure(DepCode:String;DepName:String;MyForm:TForm);TFQueryDep = class(TShadowForm)DBGridEh1: TDBGridEh;DataSource1: TDataSource;Panel1: TPanel;Label4: TLabel;Image1: TImage;Panel3: TPanel;Panel4: TPanel;DSRestConnection1: TDSRestConnection;FDMemTable1: TFDMemTable;FDStanStorageBinLink1: TFDStanStorageBinLink;FDStanStorageJSONLink1: TFDStanStorageJSONLink;FDStanStorageXMLLink1: TFDStanStorageXMLLink;procedure FormClose(Sender: TObject; var Action: TCloseAction);procedure FormDestroy(Sender: TObject);procedure DBGridEh1DblClick(Sender: TObject);procedure Image1Click(Sender: TObject);procedure FormShow(Sender: TObject);private{ Private declarations }public{ Public declarations }varUserNo:String;//用于接收上一个BPL的Form，后面调用回调过程的时候会传回去Form:TForm;end;//顶一个回调过程功能实现，用于调用上一个BPL的回调过程接收procedure PMeADD(me:MeADD);//定义上一个BPL调用过程procedure DepSetUser(sform:TForm;UserNo:String;IP:String;Port:Integer);varFQueryDep: TFQueryDep;FMeADD:MeADD;implementation
Uses Server;{$R *.dfm}
//上一个BPL调用过程的功能实现
procedure DepSetUser(sform:TForm;UserNo:String;IP:String;Port:Integer);
beginTFQueryDep(sform).UserNo:=UserNo;TFQueryDep(sform).Form:=sform;TFQueryDep(sform).DSRestConnection1.Host:=IP;TFQueryDep(sform).DSRestConnection1.Port:=Port;
end;
//用于接收传过来的过程
procedure PMeADD(me:MeADD);
beginFMeADD:=ME;
end;procedure TFQueryDep.DBGridEh1DblClick(Sender: TObject);
begin
//调用回调过程，把值和Form传回去   FMeADD(DBGridEh1.DataSource.DataSet.FieldByName('cDepCode').AsString,DBGridEh1.DataSource.DataSet.FieldByName('cDepName').AsString,Form);close;
end;procedure TFQueryDep.FormClose(Sender: TObject; var Action: TCloseAction);
begin//  Action := caFree;
end;procedure TFQueryDep.FormDestroy(Sender: TObject);
beginFQueryDep := nil;
end;procedure TFQueryDep.FormShow(Sender: TObject);
varServer: TServerMethods1Client;DSlIST: TFDJSONDataSets;
beginServer := TServerMethods1Client.Create(DSRestConnection1);DSlIST := Server.ServerGetTable('select * from Department order by cDepCode', UserNo, 1);FDMemTable1.FieldDefs.Clear;FDMemTable1.Close;FDMemTable1.Data := TFDJSONDataSetsReader.GetListValue(DSlIST, 0).Data;FDMemTable1.Open;
end;procedure TFQueryDep.Image1Click(Sender: TObject);
beginclose;
end;//给另外一个BPL获取过程使用
exportsPMeADD,DepSetUser;//给另外一个BPL获取Form使用
initializationRegisterClass(TFQueryDep);
finalizationUnRegisterClass(TFQueryDep);end.