unit1.cpp

有视频

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{
  AnsiString fieldname,filename,asstype;
  int nn;
  double aa;
  filename="test1.dbf";

  asstype="T1";
  Query1->Active=False;
  Query1->SQL->Clear();
  Query1->SQL->Add("SELECT");
  Query1->SQL->Add("MAX(NUM)");
  Query1->SQL->Add("From \""+filename+"\"");
  if(CheckBox1->Checked)
    Query1->SQL->Add("WHERE TYPE='"+asstype+"'");
  Query1->Active=True;
  nn=Query1->FieldCount;
  if(nn>0)
    fieldname=Query1->Fields->Fields[0]->FieldName;

  aa=Query1->FieldByName(fieldname)->AsFloat;
  Edit1->Text=FloatToStr(aa);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
  AnsiString fieldname,filename,asstype;
  int nn;
  double aa;
  filename="test1.dbf";

  asstype="T1";
  Query1->Active=False;
  Query1->SQL->Clear();
  Query1->SQL->Add("SELECT");
  Query1->SQL->Add("SUM(NUM)");
  Query1->SQL->Add("From \""+filename+"\"");
  if(CheckBox1->Checked)
    Query1->SQL->Add("WHERE TYPE='"+asstype+"'");
  Query1->Active=True;
  nn=Query1->FieldCount;
  if(nn>0)
    fieldname=Query1->Fields->Fields[0]->FieldName;

  aa=Query1->FieldByName(fieldname)->AsFloat;
  Edit1->Text=FloatToStr(aa);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button3Click(TObject *Sender)
{
  AnsiString fieldname,filename,asstype;
  int nn;
  double aa;
  filename="test1.dbf";

  asstype="T1";
  Query1->Active=False;
  Query1->SQL->Clear();
  Query1->SQL->Add("SELECT");
  Query1->SQL->Add("AVG(NUM)");
  Query1->SQL->Add("From \""+filename+"\"");
  if(CheckBox1->Checked)
    Query1->SQL->Add("WHERE TYPE='"+asstype+"'");
  Query1->Active=True;
  nn=Query1->FieldCount;
  if(nn>0)
    fieldname=Query1->Fields->Fields[0]->FieldName;

  aa=Query1->FieldByName(fieldname)->AsFloat;
  Edit1->Text=FloatToStr(aa);
}
//---------------------------------------------------------------------------