unit2.cpp

第一次尝试开发数据库方面的系统

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

#include <vcl.h>
#pragma hdrstop

#include "Unit2.h"
#include "Unit4.h"
#include "Unit5.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm2 *Form2;
//---------------------------------------------------------------------------
__fastcall TForm2::TForm2(TComponent* Owner)
  : TForm(Owner)
{
}
//---------------------------------------------------------------------------


void __fastcall TForm2::Button1Click(TObject *Sender)
{
  AnsiString str;
  str="select * from 读者资料 where 读者号=\'";
  str+=Edit1->Text+"\'"+" and 密码=\'";
  str+=Edit2->Text+"\'";
  if(Edit1->Text.IsEmpty()||Edit2->Text.IsEmpty())
  {
    if(Edit1->Text.IsEmpty())
    {
      ShowMessage("请输入帐号！");
      Edit1->SetFocus();
    }
    if(Edit2->Text.IsEmpty())
    {
      ShowMessage("请输入密码！");
      Edit2->SetFocus();
    }
  }
  else
  {
    try
    {
      DM->dzhQuery->Close();
      DM->dzhQuery->SQL->Clear();
      DM->dzhQuery->SQL->Add(str);
      DM->dzhQuery->ExecSQL();
      DM->dzhQuery->Active=true;
    }
    catch(Exception &exception)
    {
      ShowMessage("数据库出现错误！");
    }
    if(DM->dzhQuery->RecordCount)
    {
      TForm *Form4;
      Form4=new TForm4(this);
      Form4->ShowModal();
      delete Form4;
    }
    else
      ShowMessage("帐号或密码错误！");
  }
}
//---------------------------------------------------------------------------

void __fastcall TForm2::Button2Click(TObject *Sender)
{
  Edit1->Clear();
  Edit2->Clear();
  Edit1->SetFocus();  
}
//---------------------------------------------------------------------------

void __fastcall TForm2::Edit1KeyPress(TObject *Sender, char &Key)
{
  if(Key==VK_RETURN)
  {
    Edit2->SetFocus();
  }
}
//---------------------------------------------------------------------------

void __fastcall TForm2::Edit2KeyPress(TObject *Sender, char &Key)
{
  if(Key==VK_RETURN)
  {
    Button1Click(this);
  }
}
//---------------------------------------------------------------------------