mainform.cpp

C++ BUILDER精彩编程实例集锦(源码)3 第五部分 系统编程 第六部分 数据库应用

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

#include <vcl.h>
#pragma hdrstop

#include "Mainform.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
#include <DB.hpp>
#include <DBTables.hpp>
void __fastcall TForm1::BitBtn1Click(TObject *Sender)
{ //创建数据库
  try
  {
   TTable* newTable = new TTable(this);
   newTable->Active = false;
   newTable->DatabaseName =""; //数据库文件存放位置
   newTable->TableName ="MyDatabase.db"; //数据库文件名
   newTable->TableType = ttParadox;   //数据库类型
   //定义数据表字段类型
   newTable->FieldDefs->Clear();
   newTable->FieldDefs->Add("PID",ftInteger,0,true); //定义字段、类型、长度等
   newTable->FieldDefs->Add("No",ftString,50,false);
   newTable->FieldDefs->Add("Name",ftString,50,false);
   newTable->FieldDefs->Add("Age",ftString,50,false);
   newTable->FieldDefs->Add("Phone",ftString,50,false);
   newTable->FieldDefs->Add("Address",ftString,50,false);
   newTable->FieldDefs->Add("IDCode",ftString,50,false);
   newTable->IndexDefs->Add("","PID", TIndexOptions() <<ixPrimary << ixUnique); //定义关键字
   newTable->CreateTable(); //创建数据表
   delete newTable;
  }
  catch(...)
  {
     MessageBox(Handle,"创建数据库操作失败！","信息提示",MB_OK);
     return;
  }
  MessageBox(Handle,"创建数据库操作成功！","信息提示",MB_OK);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::BitBtn2Click(TObject *Sender)
{ //增加数据库记录
 try
 {
  Table1->DatabaseName="";
  Table1->TableName="MyDatabase.db";
  Table1->Active=true;
  Table1->Last();
  int iPID=1;
  if(Table1->IsEmpty())
     iPID=1;
  else
    iPID=Table1->FieldValues["PID"]+1;
  Table1->Append();
  Table1->FieldValues["PID"]=iPID;
  Table1->FieldValues["No"]=this->Edit1->Text;
  Table1->FieldValues["Name"]=this->Edit2->Text;
  Table1->FieldValues["Age"]=this->Edit3->Text;
  Table1->FieldValues["Phone"]=this->Edit4->Text;
  Table1->FieldValues["Address"]=this->Edit5->Text;
  Table1->FieldValues["IDCode"]=this->Edit6->Text;
  Table1->ApplyUpdates();
  Table1->CommitUpdates();
 }
 catch(...)
 {
    MessageBox(Handle,"增加数据库记录操作失败！","信息提示",MB_OK);
    return;
 }
 MessageBox(Handle,"增加数据库记录操作成功！","信息提示",MB_OK);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::BitBtn3Click(TObject *Sender)
{//查询数据库记录
  AnsiString StrName=InputBox("输入查询条件","请输入查询姓名:         ","");
  Table1->DatabaseName="";
  Table1->TableName="MyDatabase.db";
  Table1->Close();
  Table1->Filter="Name=\'";
  Table1->Filter+=StrName;
  Table1->Filter+="\'";
  Table1->Filtered=true;
  Table1->Active = true;
  if(Table1->IsEmpty())
  {
   this->Edit1->Text="";
   this->Edit2->Text="";
   this->Edit3->Text="";
   this->Edit4->Text="";
   this->Edit5->Text="";
   this->Edit6->Text="";
   MessageBox(Handle,"没有找到！","信息提示",MB_OK);
  }
  else
  {
    this->Edit1->Text=Table1->FieldValues["No"];
    this->Edit2->Text=Table1->FieldValues["Name"];
    this->Edit3->Text=Table1->FieldValues["Age"];
    this->Edit4->Text=Table1->FieldValues["Phone"];
    this->Edit5->Text=Table1->FieldValues["Address"];
    this->Edit6->Text=Table1->FieldValues["IDCode"];
  }

}

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

void __fastcall TForm1::BitBtn4Click(TObject *Sender)
{//删除数据库记录；
   if(MessageBox(Handle,"是否确认删除当前数据库记录？","信息提示",MB_YESNO)==IDNO)
      return;
   try
   {
    this->Table1->Delete();
    this->Table1->CommitUpdates();
    this->Table1->ApplyUpdates();
   }
   catch(...)
   {
    MessageBox(Handle,"请首先创建数据库！","信息提示",MB_OK);
    return;
   }
  MessageBox(Handle,"删除数据库记录操作成功！","信息提示",MB_OK);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::BitBtn5Click(TObject *Sender)
{
   this->Close();
}
//---------------------------------------------------------------------------