database.cpp

BCB 级联表的设计源代码。有需要的朋友可以看看。BCB这个东西不知道还有人用么。以往是我的最爱。

//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Database.h"
#include "Main.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
//---------------------------------------------------------------------------
extern AnsiString LoginUserName;
extern AnsiString LoginPassword;
//---------------------------------------------------------------------------
TdmeDatabase *dmeDatabase;
//---------------------------------------------------------------------------
__fastcall TdmeDatabase::TdmeDatabase(TComponent* Owner)
        : TDataModule(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TdmeDatabase::DataModuleCreate(TObject *Sender)
{
        if(!ReadRunParams())
        {
                ShowMessage("不能读取程序所需要的运行环境参数，请重试...");
                Application->Terminate();
        }
        if(!ConnectDatabase())
        {
                ShowMessage("连接数据库失败，请重试...");
                Application->Terminate();
        }
}
//---------------------------------------------------------------------------
bool __fastcall TdmeDatabase::ConnectDatabase(void)
//
//  该方法用来连接数据库
//  一般情况下，应用程序在主窗体的创建过程中不连接数据库，
//  创建完成后，调用该方法连接数据库
//
{
        try
        {
                TOpenDialog * odg = new TOpenDialog(Application);
                TStringList* slt = new TStringList();
                __try
                {
                        odg->Filter = "Text files (*.txt)|*.TXT|All files (*.*)|*.*";
                        if(!odg->Execute())
                        //  用户撤消操作，因此返回假
                                return false;
                        //  提取连接字符串
                        slt->LoadFromFile(odg->FileName);
                        dmeDatabase->acnnDatabase->ConnectionString = slt->Text;
                        //  建立连接
                        dmeDatabase->acnnDatabase->Connected = true;
                        return true;
                }
                __finally
                {
                        delete odg;
                        delete slt;
                }
        }
        catch(...)
        {
                return false;
        }
}
//---------------------------------------------------------------------------
bool __fastcall TdmeDatabase::ReadRunParams(void)
{
        return true;
}
//---------------------------------------------------------------------------
void __fastcall TdmeDatabase::acnnDatabaseLogin(TObject *Sender,
      AnsiString Username, AnsiString Password)
{
        LoginUserName = Username;
        LoginPassword = Password;        
}
//---------------------------------------------------------------------------