c++ builder 数据库开发案例

//--------------------------------------------------------------------------- #include <vcl.h> #pragma hdrstop #include "BookBorrow.h" //--------------------------------------------------------------------------- #pragma package(smart_init) #pragma resource "*.dfm" TfmBookBorrow *fmBookBorrow; //--------------------------------------------------------------------------- __fastcall TfmBookBorrow::TfmBookBorrow(TComponent* Owner) : TForm(Owner) { } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::FormShow(TObject *Sender) { // 输入读者查询条件获取焦点 edReaderCon->SetFocus(); // 设置借阅图书明细Grid的标题 StringGrid1->Cells[0][0] = "状态"; StringGrid1->Cells[1][0] = "编号"; StringGrid1->Cells[2][0] = "书名"; StringGrid1->Cells[3][0] = "借出时间"; StringGrid1->Cells[4][0] = "应还时间"; StringGrid1->Cells[5][0] = "出版社"; StringGrid1->Cells[6][0] = "书价"; } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::btOkClick(TObject *Sender) { // 保存 新借 的图书 AnsiString sql; for(int i=1; i<StringGrid1->RowCount; i++) { if(!(StringGrid1->Cells[0][i] == "新借" && StringGrid1->Cells[1][i].Length()>0)) { continue; } sql = "insert into 图书借阅(图书编号, 读者编号, 借阅时间, "; sql += "应还时间, 续借次数, 操作员, 状态) values ('"; sql += StringGrid1->Cells[1][i] + "','"; sql += edReaderCon->Text + "','"; sql += StringGrid1->Cells[3][i] + "','"; sql += StringGrid1->Cells[4][i] + "',0,'操作员','新借')"; Query1->SQL->Clear(); Query1->SQL->Add(sql); Query1->ExecSQL(); } // 调用存储过程, 减少图书库存 TQuery* pQuery = new TQuery(NULL); pQuery->DatabaseName = "db"; pQuery->SQL->Add("exec sf_图书借阅"); pQuery->ExecSQL(); delete pQuery; m_nBorrowNum = 0; m_nNum = 0; // 清空数据 edReaderCon->Text = ""; edBookCon->Text = ""; // 输入读者查询条件获取焦点 edReaderCon->SetFocus(); // 清空借阅列表 for(int i=1; i<StringGrid1->RowCount; i++) { StringGrid1->Cells[0][i] = ""; StringGrid1->Cells[1][i] = ""; StringGrid1->Cells[2][i] = ""; StringGrid1->Cells[3][i] = ""; StringGrid1->Cells[4][i] = ""; StringGrid1->Cells[5][i] = ""; StringGrid1->Cells[6][i] = ""; } Panel2->Caption = ""; } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::btCancelClick(TObject *Sender) { m_nBorrowNum = 0; m_nNum = 0; // 清空数据 edReaderCon->Text = ""; edBookCon->Text = ""; // 输入读者查询条件获取焦点 edReaderCon->SetFocus(); // 清空借阅列表 for(int i=1; i<StringGrid1->RowCount; i++) { StringGrid1->Cells[0][i] = ""; StringGrid1->Cells[1][i] = ""; StringGrid1->Cells[2][i] = ""; StringGrid1->Cells[3][i] = ""; StringGrid1->Cells[4][i] = ""; StringGrid1->Cells[5][i] = ""; StringGrid1->Cells[6][i] = ""; } Panel2->Caption = ""; } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::btExitClick(TObject *Sender) { this->Close(); } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::FormClose(TObject *Sender, TCloseAction &Action) { // 删除窗体并回收空间 Action = caFree; } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::edReaderConKeyPress(TObject *Sender, char &Key) { // 回车选择读者 if(Key == 13) { // 检查是否存在未保存的记录 for(int i=1; i<StringGrid1->RowCount; i++) { if(StringGrid1->Cells[0][i] == "新借") { Application->MessageBox("存在未保存的记录","提示",MB_OK); return; } } AnsiString szCon, sql, szReadCode; // 按照编号查询 if(rbReaderCode->Checked) szCon = "编号"; else szCon = "条形码"; szCon += "='" + edReaderCon->Text + "'"; sql = "select 姓名,类型,编号 from 读者信息 where " + szCon; Query1->SQL->Clear(); Query1->SQL->Add(sql); Query1->Open(); // 选择读者 edName->Text = Query1->FieldByName("姓名")->AsString; edType->Text = Query1->FieldByName("类型")->AsString; szReadCode = Query1->FieldByName("编号")->AsString; // 如果查询条件不正确,返回重新查询 if(edName->Text == "") { return; } // 选择该类型读者可以借阅的册书 Query1->SQL->Clear(); sql = "select 图书册书 from 读者类型 where 类型='"; sql += edType->Text + "'"; Query1->SQL->Add(sql); Query1->Open(); edNum->Text = Query1->FieldByName("图书册书")->AsString; // 将焦点跳到选择图书 edBookCon->SetFocus(); // ------------------- // 在借书列表中显示已经借出的图书 Query1->SQL->Clear(); sql = "select 图书编号,借阅时间,应还时间 from 图书借阅 "; sql += "where 状态='未还' and 读者编号='"; sql += szReadCode + "'"; Query1->SQL->Add(sql); Query1->Open(); Query1->First(); m_nBorrowNum = 0; // 清空借阅列表 for(int i=1; i<StringGrid1->RowCount; i++) { StringGrid1->Cells[0][i] = ""; StringGrid1->Cells[1][i] = ""; StringGrid1->Cells[2][i] = ""; StringGrid1->Cells[3][i] = ""; StringGrid1->Cells[4][i] = ""; StringGrid1->Cells[5][i] = ""; StringGrid1->Cells[6][i] = ""; } // 序号写入已借图书列表 while(!Query1->Eof) { // 借出册书加一 m_nBorrowNum ++; AnsiString szBookCode = Query1->FieldByName("图书编号")->AsString; Table1->Filtered = false; Table1->Filter = "编号='" + szBookCode + "'"; Table1->Filtered = true; StringGrid1->Cells[0][m_nBorrowNum] = "未还"; StringGrid1->Cells[1][m_nBorrowNum] = Table1->FieldByName("编号")->AsString; StringGrid1->Cells[2][m_nBorrowNum] = Table1->FieldByName("书名")->AsString; StringGrid1->Cells[3][m_nBorrowNum] = Query1->FieldByName("借阅时间")->AsString; StringGrid1->Cells[4][m_nBorrowNum] = Query1->FieldByName("应还时间")->AsString; StringGrid1->Cells[5][m_nBorrowNum] = Table1->FieldByName("出版社")->AsString; StringGrid1->Cells[6][m_nBorrowNum] = Table1->FieldByName("价格")->AsString; // 下一记录 Query1->Next(); } } // 设置状态条册书 Panel2->Caption = "共 " + IntToStr(m_nBorrowNum) + " 册 "; Panel2->Caption = Panel2->Caption + "本次 0 册"; } //--------------------------------------------------------------------------- void __fastcall TfmBookBorrow::edBookConKeyPress(TObject *Sender, char &Key) { // 回车选择图书 if(Key == 13) { // 检查数量是否达到限制了 if(m_nBorrowNum >= StrToInt(edNum->Text)) { Application->MessageBox("借书数量达到上限","提示",MB_OK); return; } AnsiString szCon, sql, szBookType; // 按照编号查询 if(rbBookCode->Checked) szCon = "编号"; else szCon = "条形码"; szCon += "='" + edBookCon->Text + "'"; Table1->Filtered = false;