软件工程课程设计报告模板(2)

namespace MyElectCourse.DAL {

public class Database {

protected string connectionString;

protected SqlConnection connection = null;

public Database() {

connectionString =

ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString.ToString(); }

~Database() {

if (connection != null) {

connection = null; }

}

protected void Open() {

if (connection == null) {

connection = new SqlConnection(connectionString); }

if (connection.State.Equals(ConnectionState.Closed)) {

connection.Open(); } }

protected void Close() {

if (connection != null) {

connection.Close(); } }

public int ExecuteSQL(string sqlstr) {

int count = -1; this.Open();

SqlCommand cmd = new SqlCommand(sqlstr, connection); count = cmd.ExecuteNonQuery(); this.Close();

return count; }

public DataSet GetDataSet(string sqlstr) {

this.Open();

DataSet ds = new DataSet();

SqlDataAdapter adapter = new SqlDataAdapter(sqlstr,connection); adapter.Fill(ds); this.Close();

return ds; }

public DataTable GetDataTable(string sqlstr) {

DataSet ds = this.GetDataSet(sqlstr); DataTable dt = new DataTable(); if (ds.Tables.Count > 0) {

dt = ds.Tables[0]; }

return dt; }

public SqlDataReader GetDataReader(string sqlstr) {

this.Open();

SqlCommand cmd = new SqlCommand(sqlstr, connection);

SqlDataReader sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection); //this.Close(); return sdr; } } }

5.2 UserBase类是所有系统角色用户的基类，完成用户登录验证与修改密码的功能，代码如下：

namespace MyElectCourse.BLL {

public class UserBase {

private string userID; public string UserID {

get { return userID; } set { userID = value; } }

private string userPSW; public string UserPSW {

get { return userPSW; } set { userPSW = value; } }

public string loginCheck(string uid, string upwd, string urole) {

String selectStr = String.Empty; switch (urole) {

case "0": //身份为教师时 selectStr = "Select * from Teacher where teaID = '" + uid + "'"; break;

case "1": //身份为学生时

selectStr = "Select * from Student where stuID = '" + uid + "'"; break;

case "2": //身份为管理员时

selectStr = "Select * from Users where adminName = '" + uid + "'"; break; default:

return null; }

Database db = new Database();

DataTable dt = db.GetDataTable(selectStr); if (dt.Rows.Count > 0) //如果该用户存在 {

if (dt.Rows[0][1].ToString().Equals(upwd)) //密码正确 {

switch (urole) {

case "0": //身份为教师时 return "0";

case "1": //身份为学生时 return "1";