dmunit.pas

实例4学院信息管理系统 - RAR 档案文件

unit DMUnit;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  DBTables, Db, syncobjs,
  PkgUnit;

type
  TDM = class(TDataModule)
    QueryBase: TQuery;
    DatabaseStudent: TDatabase;
    SessionStudent: TSession;
    TableSysYear: TTable;
    DBTable: TDatabase;
    TBSession: TSession;
    WkQuery: TQuery;
    WkDatabase: TDatabase;
    WkSession: TSession;
    ExecQuery: TQuery;
    ExecStoredProc: TStoredProc;
    QueryCredit: TQuery;
    QueryCourse: TQuery;
    procedure QueryBaseAfterOpen(DataSet: TDataSet);
    procedure DataModuleCreate(Sender: TObject);
    procedure DataModuleDestroy(Sender: TObject);
  private
    { Private declarations }
    nWNCritical:TCriticalSection;
    //function  getxh:string;
  public
    { Public declarations }
    procedure S_Add(const Inpkg: TSPkgData);
    procedure S_Md(const Inpkg: TSPkgData);
    procedure S_C_Add(const pStudent_id, pcourse, pcourse_t: WideString;
      pperiod, pcredit: Integer; const pbegin_date, pend_date: WideString);
    procedure S_C_Md(const pstudent_id, pcourse, pcourse_t: WideString;
      pperiod, pcredit: Integer; const pbegin_date, pend_date: WideString);
    procedure S_G_Md(const pstudent_id, pcourse: WideString; pgrades: Integer);
    procedure S_Year(const CurrentYear: WideString);    
    function  ExistData(const SQLStatment:string):boolean;
    procedure ExecSQL(const SQLStatment:string);
    function  getxh:string;
  end;

var
  DM: TDM;

implementation

{$R *.DFM}
uses  MainUnit;

procedure TDM.QueryBaseAfterOpen(DataSet: TDataSet);
begin
  { Update the query counter }
  MainForm.IncQueryCount;

end;

function  TDM.ExistData(const SQLStatment:string):boolean;
begin
  nWNCritical.Enter;
  try
    With WkQuery do
    begin
      if Active then Close;
      SQL.Clear;
      SQL.Add(SQLStatment);
      Open;
      result:=RecordCount>0;
    end;
  except
    result:=False;
  end;
  nWNCritical.Leave;
end;

procedure TDM.ExecSQL(const SQLStatment:string);
begin
  nWNCritical.Enter;
  try
    with ExecQuery do
    begin
      if Active then Close;
      SQL.Clear;
      SQL.Add(SQLStatment);
      ExecSQL;
    end;
  except
    Raise;
  end;
  nWNCritical.Leave;
end;

function  TDM.getxh:string;
var  s:string;
begin
  {1.取学号}
  nWNCritical.Enter;
  With ExecStoredProc do
  begin
    StoredProcName := 'newwks';
    ParamBindMode :=pbByName;
    Params.Clear;
    Params.CreateParam(ftString, 'STUDENT_NAME', ptInput);
    Params.CreateParam(ftString, 'STUDENT_ID', ptOutput);

    ParamByName('STUDENT_NAME').AsString := 'Name';

    ExecProc;
    GetResults;
    s:=ParamByName('STUDENT_ID').AsString;
  end;
  Result:=S;
  nWNCritical.Leave;
end;

procedure TDM.S_Add(const Inpkg: TSPkgData);
var pkg:TSPackage;
    fstudent_id: string[8]; //*学号*/
    fname: string[12];//*学员姓名*/
    fsex: string[1];//*性别*/
    fgrade: string[4];//*入学年度*/
    fnative: string[20];//*籍贯*/
    fidentity: string[18];//*身份证编号*/
    fage: string; //*年龄*/
begin
  pkg := TSPackage.Create(Inpkg);
  {拆解数据包}
  with pkg do
  begin
    fname      := Item['name']; //*学员姓名*/
    fsex       := Item['sex']; //*性别*/
    fgrade     := Item['grade']; //*入学年度*/
    fnative    := Item['native']; //*籍贯*/
    fidentity  := Item['identity']; //*身份证编号*/
    fage       := Item['age']; //*年龄*/
  end;
  pkg.Free;

  {分析数据 ... }

  {取新的学号}
  fstudent_id:=getxh;
  {插入数据库 ... }

  ExecSQL('Insert into BaseTB(student_id,name,sex,grade,native,identity,age) '+
  'Values('+
  QuotedStr(fstudent_id)+','+
  QuotedStr(fname)+','+
  QuotedStr(fsex)+','+
  QuotedStr(fgrade)+','+
  QuotedStr(fnative)+','+
  QuotedStr(fidentity)+','+
  fage+')' );

{
  fstudent_id: string[8]; //*学号*/
  fname:= string[12];//*学员姓名*/
  fsex: string[1];//*性别*/
  fgrade: string[4];//*入学年度*/
  fnative: string[20];//*籍贯*/
  fidentity: string[18];//*身份证编号*/
  fage: integer; //*年龄*/
}

end;

procedure TDM.S_Md(const Inpkg: TSPkgData);
var pkg:TSPackage;
    fstudent_id: string[8]; //*学号*/
    fname: string[12];//*学员姓名*/
    fsex: string[1];//*性别*/
    fgrade: string[4];//*入学年度*/
    fnative: string[20];//*籍贯*/
    fidentity: string[18];//*身份证编号*/
    fage: string; //*年龄*/
    s:string;
begin
  pkg := TSPackage.Create(Inpkg);
  {拆解数据包}
  with pkg do
  begin
    fstudent_id:= Item['student_id']; //*学号*/
    fname      := Item['name']; //*学员姓名*/
    fsex       := Item['sex']; //*性别*/
    fgrade     := Item['grade']; //*入学年度*/
    fnative    := Item['native']; //*籍贯*/
    fidentity  := Item['identity']; //*身份证编号*/
    fage       := Item['age']; //*年龄*/
  end;
  pkg.Free;

  {分析数据 ... }

  {插入数据库 ... }
  s:='Update BaseTB Set '+
     ' name='+QuotedStr(fname)+','+
     ' sex='+QuotedStr(fsex)+','+
     ' grade='+QuotedStr(fgrade)+','+
     ' native='+QuotedStr(fnative)+','+
     ' identity='+QuotedStr(fidentity)+','+
     ' age='+fage+
     ' where student_id='+QuotedStr(fstudent_id) ;

  ExecSQL(s);

end;


procedure TDM.DataModuleCreate(Sender: TObject);
begin
  {}
  nWNCritical:=TCriticalSection.Create;
end;

procedure TDM.DataModuleDestroy(Sender: TObject);
begin
  nWNCritical.Free;
end;

procedure TDM.S_C_Add(const pStudent_id, pcourse, pcourse_t: WideString;
      pperiod, pcredit: Integer; const pbegin_date, pend_date: WideString);
begin
  if not ExistData('select * from CourseTB where student_id='+QuotedStr(pstudent_id)+' and course='+QuotedStr(pcourse) ) then
  begin
    ExecSQL('insert into CourseTB(student_id,course,course_t,period,credit,begin_date,end_date)'+
      ' values('+
       QuotedStr(pStudent_id)+','+
       QuotedStr(pcourse)+','+
       QuotedStr(pcourse_t)+','+
       inttostr(pperiod)+','+
       inttostr(pcredit)+','+
       QuotedStr(pbegin_date)+','+
       QuotedStr(pend_date)+')');

    {插入成绩，单初值为0}
    ExecSQL('insert into CreditTB(student_id,course,grades)'+
       ' values('+
       QuotedStr(pStudent_id)+','+
       QuotedStr(pcourse)+',0)');
  end;

end;

procedure TDM.S_C_Md(const pstudent_id, pcourse, pcourse_t: WideString;
      pperiod, pcredit: Integer; const pbegin_date, pend_date: WideString);
begin
  if ExistData('select * from CourseTB where student_id='+QuotedStr(pstudent_id)+' and course='+QuotedStr(pcourse) ) then
  ExecSQL('Update CourseTB Set '+
     ' course_t='+QuotedStr(pcourse_t)+','+
     ' period='+ inttostr(pperiod)+','+
     ' credit='+ inttostr(pcredit)+','+
     ' begin_date='+ QuotedStr(pbegin_date)+','+
     ' end_date='+ QuotedStr(pend_date)+
     ' where student_id='+QuotedStr(pstudent_id)+
     ' and course='+QuotedStr(pcourse) );

end;

procedure TDM.S_G_Md(const pstudent_id, pcourse: WideString; pgrades: Integer);
begin
  ExecSQL('Update CreditTB Set grades='+ inttostr(pgrades)+
     ' where student_id='+QuotedStr(pstudent_id)+
     ' and course='+QuotedStr(pcourse) );
end;

procedure TDM.S_Year(const CurrentYear: WideString);
begin
  ExecSQL('Update SysPramTB Set PaMa='+ QuotedStr(CurrentYear)+
     ' where pmky='+QuotedStr('student')+
     ' and cdky='+QuotedStr('grade') );
end;

end.