unit4.cpp

数据库管理

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

#include <vcl.h>
#pragma hdrstop

#include "Unit4.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm4 *Form4;
//---------------------------------------------------------------------------
__fastcall TForm4::TForm4(TComponent* Owner)
    : TForm(Owner)
{
}
//---------------------------------------------------------------------------

void __fastcall TForm4::Button1Click(TObject *Sender)//插入新类型
{
    if(Table1->Active==false)
      Table1->Open();
    if(Edit1->Text==""||Edit2->Text=="")
      MessageBox(NULL,"请输入完整信息","信息",MB_OK);
    else{
         Table1->First();
         int i=0;
     while(!(Table1->Eof)&&(i==0))
     {
       if(Table1->FieldByName("类型")->Value==Edit1->Text)
         { MessageBox(NULL,"该类型已存在","信息",MB_OK);
           i++;
          }
       Table1->Next();
     }
           if(i==0){
           Table1->Append();
           Table1->FieldByName("类型")->Value=Edit1->Text;
           Table1->FieldByName("分值")->Value=StrToFloat(Edit2->Text);
           Table1->Post();
           Edit1->Text="";
           Edit2->Text="";
           MessageBox(NULL,"信息以插入","信息",MB_OK);
           }
      }
}
//---------------------------------------------------------------------------
void __fastcall TForm4::Button2Click(TObject *Sender)//修改
{
   if(Table1->Active==false)
      Table1->Open();
   if( Edit1->Text=="")
      MessageBox(NULL,"请输入要修改的类型","信息",MB_OK);
   else{
   Table1->First();
     int i=0;
     while(!(Table1->Eof)&&(i==0))
     {
       if(Table1->FieldByName("类型")->Value==Edit1->Text)
         { Table1->Edit();
           Table1->FieldByName("分值")->Value=StrToFloat(Edit2->Text);
           Table1->Post();
           MessageBox(NULL,"信息已修改","信息",MB_OK);
           i++;
          }
       Table1->Next();
     }

     }

}
//---------------------------------------------------------------------------
void __fastcall TForm4::Button4Click(TObject *Sender)
{
    Close();
}
//---------------------------------------------------------------------------
void __fastcall TForm4::Button3Click(TObject *Sender)//删除
{
   if(Table2->Active==false)
      Table2->Open();
   Table2->IndexFieldNames="类型";
   Table2->SetKey();
   Table2->FieldByName("类型")->Value=Edit1->Text;
   if(!Table2->GotoKey())
   {
   if(Table1->Active==false)
      Table1->Open();
   Table1->First();
     int i=0;
     while(!(Table1->Eof)&&(i==0))
     {
       if(Table1->FieldByName("类型")->Value==Edit1->Text)
         {

           Table1->Delete();
           MessageBox(NULL,"信息已删除","信息",MB_OK);
           Edit1->Text="";
           Edit2->Text="";
           i++;
          }
       Table1->Next();
     }
     }
     else
          MessageBox(NULL,"在活动查询表中有相关信息正在使用，不能删除","",MB_OK);

}
//---------------------------------------------------------------------------