应用抽象工厂+反射实现通用数据源的设计（一）
上一篇博客提到了.net的架构模式，主要写了普通的实现和OOP思想的三层模式，当然有一定的弊端，这篇博文主要是通过对学生表的操作实现抽象工厂+反射通用数据源的设计。
一：Model层对实体类的封装：
public int Sid { get; set; }
public string Sname { get; set; }
public string StuSex { get; set; }
public string StuAdd { get; set; }
二：DBLibrary 访问数据库的两个类进行分装：SqlServer和Access
1.SQLHelper：
private static readonly string ConnectionString = ConfigurationManager.AppSettings["conn"].ToString();
//SqlParameter[] 方便传递数组
/// <summary>
/// 主要用于封装Command对象的ExecuteNonQuery方法,用于数据的增删改
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回受影响的行数</returns>
public static int ExecuteNonQuery(string cmdText, CommandType cmdType, params SqlParameter[] cmdParams)
{
SqlConnection conn = new SqlConnection(ConnectionString);
SqlCommand comm = new SqlCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
return comm.ExecuteNonQuery();
}
catch (SqlException ex)
{
throw ex;
}
finally {
conn.Close();
}
}
/// <summary>
/// 封装Command对象的ExecuteReader 方法用于数据的查询
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回SqlDataReader对象</returns>
public static SqlDataReader ExcuteReader(string cmdText, CommandType cmdType, params SqlParameter[] cmdParams)
{
SqlConnection conn = new SqlConnection(ConnectionString);
SqlCommand comm = new SqlCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
//自动关闭
return comm.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (SqlException ex)
{
throw ex;
}
}
/// <summary>
/// 封装Commond对象的ExecuteScalar方法，用于返回首行首列数据
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回的是object单一的值</returns>
public static object ExecuteScalar(string cmdText, CommandType cmdType, params SqlParameter[] cmdParams)
{
SqlConnection conn = new SqlConnection(ConnectionString);
SqlCommand comm = new SqlCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
return comm.ExecuteScalar();
}
catch (SqlException ex)
{
throw ex;
}
finally
{
conn.Close();
}
}
/// <summary>
/// 主要用于返回DataTable 查询的数据
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回DataTable对象</returns>
public static DataTable GetDataTable(string cmdText, CommandType cmdType, params SqlParameter[] cmdParams)
{
SqlConnection conn = new SqlConnection();
SqlCommand comm = new SqlCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = comm;
DataSet ds = new DataSet();
try
{
//自动打开自动关闭 实现断开式的链接
da.Fill(ds);
return ds.Tables[0];
}
catch (SqlException ex)
{
throw ex;
}
finally {
conn.Close();
}
}
/// <summary>
/// 主要用于给Command对象进行初始化赋值工作
/// </summary>
/// <param name="comm">是操作的Comman对象</param>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
private static void PrepareCommand(SqlCommand comm, SqlConnection conn, string cmdText, CommandType cmdType, SqlParameter[] cmdParams)
{
if (conn.State == ConnectionState.Closed) conn.Open();
comm.Connection = conn;
comm.CommandText = cmdText;
comm.CommandType = cmdType;
if (cmdParams != null)
{
for (int i = 0; i < cmdParams.Length; i++)
{
comm.Parameters.Add(cmdParams[i]);
}
}
}
2.AccessHelper
public class AccessHelper
{
private static readonly string ConnectionString = ConfigurationManager.AppSettings["conn"].ToString();
//SqlParameter[] 方便传递数组
/// <summary>
/// 主要用于封装Command对象的ExecuteNonQuery方法,用于数据的增删改
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回受影响的行数</returns>
public static int ExecuteNonQuery(string cmdText, CommandType cmdType, params OleDbParameter[] cmdParams)
{
OleDbConnection conn = new OleDbConnection(ConnectionString);
OleDbCommand comm = new OleDbCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
return comm.ExecuteNonQuery();
}
catch (OleDbException ex)
{
throw ex;
}
finally
{
conn.Close();
}
}
/// <summary>
/// 封装Command对象的ExecuteReader 方法用于数据的查询
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回SqlDataReader对象</returns>
public static OleDbDataReader ExcuteReader(string cmdText, CommandType cmdType, params OleDbParameter[] cmdParams)
{
OleDbConnection conn = new OleDbConnection(ConnectionString);
OleDbCommand comm = new OleDbCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
//自动关闭
return comm.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (OleDbException ex)
{
throw ex;
}
}
/// <summary>
/// 封装Commond对象的ExecuteScalar方法，用于返回首行首列数据
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回的是object单一的值</returns>
public static object ExecuteScalar(string cmdText, CommandType cmdType, params OleDbParameter[] cmdParams)
{
OleDbConnection conn = new OleDbConnection(ConnectionString);
OleDbCommand comm = new OleDbCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
try
{
return comm.ExecuteScalar();
}
catch (OleDbException ex)
{
throw ex;
}
finally
{
conn.Close();
}
}
/// <summary>
/// 主要用于返回DataTable 查询的数据
/// </summary>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
/// <returns>返回DataTable对象</returns>
public static DataTable GetDataTable(string cmdText, CommandType cmdType, params OleDbParameter[] cmdParams)
{
OleDbConnection conn = new OleDbConnection(ConnectionString);
OleDbCommand comm = new OleDbCommand();
PrepareCommand(comm, conn, cmdText, cmdType, cmdParams);
OleDbDataAdapter da = new OleDbDataAdapter();
da.SelectCommand = comm;
DataSet ds = new DataSet();
try
{
//自动打开自动关闭 实现断开式的链接
da.Fill(ds);
return ds.Tables[0];
}
catch (OleDbException ex)
{
throw ex;
}
finally
{
conn.Close();
}
}
/// <summary>
/// 主要用于给Command对象进行初始化赋值工作
/// </summary>
/// <param name="comm">是操作的Comman对象</param>
/// <param name="conn">Connection对象</param>
/// <param name="cmdText">Command.CommandText</param>
/// <param name="cmdType">Command.CommandType</param>
/// <param name="cmdParams">Command.Parameters</param>
private static void PrepareCommand(OleDbCommand comm, OleDbConnection conn, string cmdText, CommandType cmdType, OleDbParameter[] cmdParams)
{
if (conn.State == ConnectionState.Closed) conn.Open();
comm.Connection = conn;
comm.CommandText = cmdText;
comm.CommandType = cmdType;
if (cmdParams != null)
{
for (int i = 0; i < cmdParams.Length; i++)
{
comm.Parameters.Add(cmdParams[i]);
}
}
}
}
三：定义一个学生表的接口（引用model实体层）：
public interface IStudent
{
IList<Student> GetAllStudents();
Student GetStudent(int stuno);
IList<Student> GetStudentByName(string stuname);
int AddStudnet(Student student);
int ModifyStudent(Student student);
int DelStudetnt(int stuno);
}
四：1.让SqlServerDal中实现StudentServer学生表接口中的方法（引用Model和DBLibrary，修改调用的存储过程）：
public class StudentServer:IStudent
{
private IList<Student> GetStudentBySQL(string strsql,params SqlParameter[] cmdParams)
{
IList<Student> list = new List<Student>();
using (SqlDataReader dr = SQLHelper.ExcuteReader(strsql, CommandType.Text, cmdParams))
{
while (dr.Read())
{
Student student = new Student();
student.Sid = dr.GetInt32(0);
student.Sname = dr.GetString(1);
student.StuSex = dr.GetString(2);
student.StuAdd = dr.GetString(3);
list.Add(student);
}
return list;
}
}
/// <summary>
/// 得到所有的学生信息
/// </summary>
/// <returns></returns>
public IList<Student> GetAllStudents()
{
string strsql = "select * from Student";
return this.GetStudentBySQL(strsql,null);
}
/// <summary>
/// 根据主建ID查询学生
/// </summary>
/// <param name="stuno"></param>
/// <returns></returns>
public Student GetStudent(int stuno)
{
string strsql = "select * from Student where Sid=@stuno";
SqlParameter param_id = new SqlParameter();
param_id.ParameterName = "@stuno";
param_id.SqlDbType = SqlDbType.Int;
param_id.Value = stuno;
IList<Student> students = this.GetStudentBySQL(strsql, param_id);
if (students != null && students.Count > 0)
{
return students[0];
}
else {
return null;
}
}
/// <summary>
/// 根据学生的姓名进行查询
/// </summary>
/// <param name="stuname"></param>
/// <returns></returns>
public IList<Student> GetStudentByName(string stuname)
{
string paramStuName=string.Format("%{0}%",stuname);
string strsql = "select * from Student where like @stuname";
SqlParameter param_name = new SqlParameter();
param_name.ParameterName = stuname;
param_name.SqlDbType = SqlDbType.VarChar;
//与数据库对应
param_name.Size = 50;
param_name.Value = paramStuName;
return this.GetStudentBySQL(strsql, param_name);
}
/// <summary>
/// 添加一个学生
/// </summary>
/// <param name="student"></param>
/// <returns></returns>
public int AddStudnet(Student student)
{
string strsql = @"INSERT INTO [dbo].[Student]
([StuName]
,[StuSex]
,[StuAddr])
VALUES
(@stuName
,@stuSex,
,@stuAddr)";
SqlParameter param_name = new SqlParameter("@stuName",SqlDbType.VarChar,50);
param_name.Value = student.Sname;
SqlParameter param_sex = new SqlParameter("@stuSex", SqlDbType.VarChar, 2);
param_name.Value = student.StuSex;
SqlParameter param_addr = new SqlParameter("@stuAddr", SqlDbType.VarChar, 100);
param_name.Value = student.StuAdd;
return SQLHelper.ExecuteNonQuery(strsql, CommandType.Text, param_name, param_sex, param_addr);
}
/// <summary>
/// 修改一个学生
/// </summary>
/// <param name="student"></param>
/// <returns>代表受影响的行数</returns>
public int ModifyStudent(Student student)
{
string strsql = "pro_ModifyStudent";
SqlParameter param_id = new SqlParameter("@@stuno", SqlDbType.Int);
param_id.Value = student.Sid;
//默认为Input 输入类型
param_id.Direction = ParameterDirection.Input;
SqlParameter param_name = new SqlParameter("@stuName", SqlDbType.VarChar, 50);
param_name.Value = student.Sname;
param_name.Direction = ParameterDirection.Input;
SqlParameter param_sex = new SqlParameter("@stuSex", SqlDbType.VarChar, 2);
param_sex.Value = student.StuSex;
param_sex.Direction = ParameterDirection.Input;
SqlParameter param_addr = new SqlParameter("@stuAddr", SqlDbType.VarChar, 100);
param_addr.Value = student.StuAdd;
param_addr.Direction = ParameterDirection.Input;
SqlParameter param_return = new SqlParameter("@returnValueParams", SqlDbType.Int);
//存储过程返回值的类型
param_return.Direction = ParameterDirection.ReturnValue;
SQLHelper.ExecuteNonQuery(strsql, CommandType.StoredProcedure, param_id, param_name, param_sex, param_addr, param_return);
return (int)param_return.Value;
}
/// <summary>
/// 删除一个学生
/// </summary>
/// <param name="stuno"></param>
/// <returns></returns>
public int DelStudetnt(int stuno)
{
string strsql = "delete from Student where stuno=@stuno";
SqlParameter param_id = new SqlParameter();
param_id.ParameterName = "@stuno";
param_id.SqlDbType = SqlDbType.Int;
param_id.Value = stuno;
return SQLHelper.ExecuteNonQuery(strsql, CommandType.Text, param_id);
}
}
2.AccessDal中实现StudentServer学生表接口中的方法（引用Model和DBLibrary，Access数据库中没有int类型 为TinyInt）
public class StudentServer : IStudent
{
private IList<Student> GetStudentBySQL(string strsql, params OleDbParameter[] cmdParams)
{
IList<Student> list = new List<Student>();
using (OleDbDataReader dr = AccessHelper.ExcuteReader(strsql, CommandType.Text, cmdParams))
{
while (dr.Read())
{
Student student = new Student();
student.Sid = dr.GetInt32(0);
student.Sname = dr.GetString(1);
student.StuSex = dr.GetString(2);
student.StuAdd = dr.GetString(3);
list.Add(student);
}
return list;
}
}
/// <summary>
/// 得到所有的学生信息
/// </summary>
/// <returns></returns>
public IList<Student> GetAllStudents()
{
string strsql = "select * from Student";
return this.GetStudentBySQL(strsql, null);
}
/// <summary>
/// 根据主建ID查询学生
/// </summary>
/// <param name="stuno"></param>
/// <returns></returns>
public Student GetStudent(int stuno)
{
string strsql = "select * from Student where Sid=@stuno";
OleDbParameter param_id = new OleDbParameter();
param_id.ParameterName = "@stuno";
param_id.OleDbType = OleDbType.Integer;
param_id.Value = stuno;
IList<Student> students = this.GetStudentBySQL(strsql, param_id);
if (students != null && students.Count > 0)
{
return students[0];
}
else
{
return null;
}
}
/// <summary>
/// 根据学生的姓名进行查询
/// </summary>
/// <param name="stuname"></param>
/// <returns></returns>
public IList<Student> GetStudentByName(string stuname)
{
string paramStuName = string.Format("%{0}%", stuname);
string strsql = "select * from Student where like @stuname";
OleDbParameter param_name = new OleDbParameter();
param_name.ParameterName = stuname;
param_name.OleDbType = OleDbType.VarChar;
//与数据库对应
param_name.Size = 50;
param_name.Value = paramStuName;
return this.GetStudentBySQL(strsql, param_name);
}
/// <summary>
/// 添加一个学生
/// </summary>
/// <param name="student"></param>
/// <returns></returns>
public int AddStudnet(Student student)
{
string strsql = @"INSERT INTO [dbo].[Student]
([StuName]
,[StuSex]
,[StuAddr])
VALUES
(@stuName
,@stuSex,
,@stuAddr)";
OleDbParameter param_name = new OleDbParameter("@stuName", OleDbType.VarChar, 50);
param_name.Value = student.Sname;
OleDbParameter param_sex = new OleDbParameter("@stuSex", OleDbType.VarChar, 2);
param_name.Value = student.StuSex;
OleDbParameter param_addr = new OleDbParameter("@stuAddr", OleDbType.VarChar, 100);
param_name.Value = student.StuAdd;
return AccessHelper.ExecuteNonQuery(strsql, CommandType.Text, param_name, param_sex, param_addr);
}
/// <summary>
/// 修改一个学生
/// </summary>
/// <param name="student"></param>
/// <returns>代表受影响的行数</returns>
public int ModifyStudent(Student student)
{
string strsql = @"UPDATE [dbo].[Student]
SET
[StuName]=@stuName
,[StuSex]=@stuSex
,[StuAddr]=@stuAddr
WHERE StuNo=@stuno";
OleDbParameter param_id = new OleDbParameter("@@stuno", OleDbType.TinyInt);
param_id.Value = student.Sid;
//默认为Input 输入类型
param_id.Direction = ParameterDirection.Input;
OleDbParameter param_name = new OleDbParameter("@stuName", OleDbType.VarChar, 50);
param_name.Value = student.Sname;
param_name.Direction = ParameterDirection.Input;
OleDbParameter param_sex = new OleDbParameter("@stuSex", OleDbType.VarChar, 2);
param_sex.Value = student.StuSex;
param_sex.Direction = ParameterDirection.Input;
OleDbParameter param_addr = new OleDbParameter("@stuAddr", OleDbType.VarChar, 100);
param_addr.Value = student.StuAdd;
param_addr.Direction = ParameterDirection.Input;
return AccessHelper.ExecuteNonQuery(strsql, CommandType.StoredProcedure, param_id, param_name, param_sex, param_addr);
}
/// <summary>
/// 删除一个学生
/// </summary>
/// <param name="stuno"></param>
/// <returns></returns>
public int DelStudetnt(int stuno)
{
string strsql = "delete from Student where stuno=@stuno";
OleDbParameter param_id = new OleDbParameter();
param_id.ParameterName = "@stuno";
param_id.OleDbType = OleDbType.Integer;
param_id.Value = stuno;
return AccessHelper.ExecuteNonQuery(strsql, CommandType.Text, param_id);
}
}
注意：Access中引用的是System.Data.OleDb;的命名空间
