enterscore.pas

delphi 学生选课系统的实现 附有sql 语句

unit EnterScore;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Grids, DBGrids, DBCtrls;

type
  TEnterScoreForm = class(TForm)
    DBGrid1: TDBGrid;
    Label1: TLabel;
    ComboBox1: TComboBox;
    Label2: TLabel;
    ComboBox2: TComboBox;
    Label3: TLabel;
    Edit1: TEdit;
    Label4: TLabel;
    Label5: TLabel;
    Edit2: TEdit;
    Edit3: TEdit;
    Button1: TButton;
    procedure OnShow(Sender: TObject);
    procedure ComboBox1Change(Sender: TObject);
    procedure OnHide(Sender: TObject);
    procedure ComboBox2Change(Sender: TObject);
    procedure OnCellClick(Column: TColumn);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  EnterScoreForm: TEnterScoreForm;

implementation

uses DataModule,Login;

{$R *.dfm}

procedure TEnterScoreForm.OnShow(Sender: TObject);
begin
  with DataModuleForm.A_Tea_Query do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select distinct 课程号 from 课程详细信息');
    SQL.Add('where 教师编号 = '+''''+Login.UseId+'''');
    Open;
    if recordcount > 0 then
    begin
      First;
      while not Eof do
      begin
        ComboBox1.Items.Add(FieldByName('课程号').AsString);
        Next;
      end;
    end;
  end
end;

procedure TEnterScoreForm.ComboBox1Change(Sender: TObject);
begin
  with DataModuleForm.A_Tea_Query do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select distinct 课序号 from 课程详细信息');
    SQL.Add('where 课程号 = '+''''+ComboBox1.Text+'''');
    Open;
    ComboBox2.Items.clear;
    ComboBox2.Text := '';
    Edit1.Text := '';
    Edit2.Text := '';
    Edit3.Text := '';
    if recordcount > 0 then
    begin
      First;
      while not Eof do
      begin
        ComboBox2.Items.Add(FieldByName('课序号').AsString);
        Next;
      end;
    end;
  end
end;

procedure TEnterScoreForm.OnHide(Sender: TObject);
begin
  ComboBox1.Clear;
  ComboBox2.Clear;
  ComboBox1.Text := '';
  ComboBox2.Text := '';
  Edit1.Text := '';
  Edit2.Text := '';
  Edit3.Text := '';
end;

procedure TEnterScoreForm.ComboBox2Change(Sender: TObject);
begin
  with DataModuleForm.A_Tea_Query do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select 课程名 from 课程详细信息');
    SQL.Add('where 课程号 = '+''''+ComboBox1.Text+'''');
    SQL.Add('and 课序号 = '+''''+ComboBox2.Text+'''');
//    Application.MessageBox(SQL.GetText,'信息',MB_OK);
    Open;
    Edit1.Text := FieldByName('课程名').AsString;
  end;

  with DataModuleForm.A_Tea_Display do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select * from 学生选课信息');
    SQL.Add('where 课程号 = '+''''+ComboBox1.Text+'''');
    SQL.Add('and 课序号 = '+''''+ComboBox2.Text+'''');
 //   Application.MessageBox(SQL.GetText,'信息',MB_OK);
    Open;
  end;
end;

procedure TEnterScoreForm.OnCellClick(Column: TColumn);
begin
  Edit2.Text := DataModuleForm.A_Tea_Display.FieldByName('学号').AsString;
  Edit3.Text := DataModuleForm.A_Tea_Display.FieldByName('成绩').AsString;
end;

procedure TEnterScoreForm.Button1Click(Sender: TObject);
begin
  with DataModuleForm.A_Tea_Score do
  begin
    Close;
    SQL.Clear;
    SQL.Add('update 学生选课信息');
    SQL.Add('set 成绩 = '+Edit3.Text);
    SQL.Add('where 学号 = '+Edit2.Text);
    SQL.Add('and 课程号 = '+ComboBox1.Text);
    SQL.Add('and 课序号 = '+ComboBox2.Text);
//    Application.MessageBox(SQL.GetText,'信息',MB_OK);
    ExecSQL;
    Application.MessageBox('成绩添加/修改成功！','信息',MB_OK);
    Edit2.Text := '';
    Edit3.Text := '';
  end;

  with DataModuleForm.A_Tea_Display do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select * from 学生选课信息');
    SQL.Add('where 课程号 = '+''''+ComboBox1.Text+'''');
    SQL.Add('and 课序号 = '+''''+ComboBox2.Text+'''');
//   Application.MessageBox(SQL.GetText,'信息',MB_OK);
    Open;
  end;
end;

end.