unit2.pas

学生宿舍管理系统,用于宿舍的信息管理,简单容易用.

unit Unit2;

interface

uses
  SysUtils, Classes, DB, ADODB;

type
  TDataModule2 = class(TDataModule)
    ADOConnection1: TADOConnection;
    procedure DataModuleCreate(Sender: TObject);
    function CheckUserName(username :string):boolean;
    function CheckUserPassword(username,userpassword :string):boolean;
    function AddUser(username,userpassword,jibie :string):boolean;
    function DeleteUser(username:string):boolean;
    function ReturnType(username,userpassword:string):String;
    function EditUserPassword(username,oldpassword,newpassword :string):boolean;
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  DataModule2: TDataModule2;

implementation

{$R *.dfm}
                                 //连接数据库
procedure TDataModule2.DataModuleCreate(Sender: TObject);
begin
ADOConnection1.ConnectionString :='Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+getcurrentdir+'\house.mdb;Persist Security Info=True;Jet OLEDB:Database Password=hjp';
ADOConnection1.Open();
end;
//ADOConnection1.ConnectionString :='Provider=Microsoft.Jet.OLEDB.4.0;Password="";Persist Security Info=False';

                       //检查用户名正确否
function TDataModule2.CheckUserName(username :string):boolean;

var
    Query :TADOQuery;

begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;
  Query.SQL.Text :='select * from 用户表 where 用户名=:name';
  Query.Parameters.ParamByName('name').Value :=username;
  
  Query.Open ;

  if Query.RecordCount =1 then
    result :=true
  else
    result :=false;

  Query.Close ;
  Query.Free ;
end;
                         //检查用户密码正确否
function TDataModule2.CheckUserPassword(username,userpassword :string):boolean;

var
  Query :TADOQuery;
begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;
  Query.SQL.Text :='select * from 用户表 where 用户名=:name';
  Query.Parameters.ParamByName('name').Value :=username;
  Query.Open ;

  if Query.fieldByName('密码').Value =userpassword then
    result :=true
  else
    result :=false;

  Query.Close;
  Query.Free ;
end;                     //返回用户级别

function TDataModule2.ReturnType(username,userpassword:string):String ;
var
  Query :TADOQuery;
begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;
  Query.SQL.Text :='select * from 用户表 where 用户名=:name and 密码=:password';
  Query.Parameters.ParamByName('name').Value :=username;
  Query.Parameters.ParamByName('password').Value :=userpassword;
  Query.Open ;

  if Query.RecordCount=1 then
    result :=Query.fieldByName('级别').Value
  else
    result :='0';

  Query.Close;
  Query.Free ;
end;
                         //添加用户
function TDataModule2.AddUser(username,userpassword,jibie :string):boolean;
var
  Query :TADOQuery;
begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;

  Query.SQL.Clear ;
  Query.SQL.Text :='insert into 用户表 (用户名,密码,级别) values (:name,:password,:jb)';
  Query.Parameters.ParamByName('name').Value :=username;
  Query.Parameters.ParamByName('password').Value :=userpassword;
  Query.Parameters.ParamByName('jb').Value :=jibie;
  Query.Prepared ;

  try
  ADOConnection1.BeginTrans;
  Query.ExecSQL ;
  ADOConnection1.CommitTrans;
  result :=true;
  except
    ADOConnection1.RollBackTrans;
    result :=false;
  end;

  Query.Close ;
  Query.Free ;

end;

                          //删除用户
function TDataModule2.DeleteUser(username :string):boolean;
var
  Query :TADOQuery;
begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;

    Query.SQL.Clear ;
    Query.SQL.Text :='delete from 用户表 where 用户名=:name';
    Query.Parameters.ParamByName('name').Value :=username;
    Query.Prepared ;
    Query.ExecSQL ;

    try
    ADOConnection1.BeginTrans ;
    ADOConnection1.CommitTrans ;
    result :=true;
    except
       ADOConnection1.RollbackTrans;
       result :=false;
    end;

  Query.Close ;
  Query.Free ;
end;

                              //修改用户密码
function TDataModule2.EditUserPassword(username,oldpassword,newpassword :string):boolean;
var
  Query :TADOQuery;
begin
  Query :=TADOQuery.Create(self);
  Query.Connection :=ADOConnection1;

  Query.SQL.Clear ;
  Query.SQL.Text :='update 用户表 set 密码=:newword  where 用户名=:name and 密码=:oldword';
  Query.Parameters.ParamByName('newword').Value :=newpassword;
  Query.Parameters.ParamByName('name').Value :=username;
  Query.Parameters.ParamByName('oldword').Value :=oldpassword;
  Query.Prepared ;

  try
  ADOConnection1.BeginTrans;
  Query.ExecSQL ;
  ADOConnection1.CommitTrans;
  result :=true;
  except
    ADOConnection1.RollBackTrans;
    result :=false;
  end;

  Query.Close ;
  Query.Free ;
end;
end.