泛型连接数据库

这些天用泛型做了一个数据库的底层，自我感觉很方便，但是功能不是很完善，会继续考虑下去下面给大家分享一下代码

1数据库连接的帮助类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SqlClient;

namespace DAL
{

    public class DBHelper
    {
        /// <summary>
        /// 从web.config中获得数据库连接字符串
        /// </summary>
        public static string Connstr = "Data Source=.;Initial Catalog=Pet;Integrated Security=True";

        #region sql语句部分


        /// <summary>
        /// 执行sql语句返回DataTable
        /// </summary>
        /// <param name="sql">sql</param>
        /// <returns>根据sql语句得到所有记录</returns>
        public static DataTable GetDataTable(string sql)
        {

            using (SqlConnection conn = new SqlConnection(Connstr))
            {

                SqlDataAdapter sda = new SqlDataAdapter(sql, conn);
                DataTable dt = new DataTable();
                sda.Fill(dt);
                return dt;


            }


        }

        /// <summary>
        /// 执行带参数的sql语句返回DataTable
        /// </summary>
        /// <param name="sql">带参数的sql语句</param>
        /// <param name="values">参数</param>
        /// <returns>根据sql语句得到所有记录</returns>
        public static DataTable GetDataTable(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                conn.Open();
                cmd.Parameters.AddRange(values);
                SqlDataAdapter sda = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                sda.Fill(dt);
                conn.Close();
                return dt;
            }


        }


        /// <summary>
        /// 执行无参数的sql语句
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteCommand(string sql)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                conn.Open();
                int num = cmd.ExecuteNonQuery();
                conn.Close();
                return num;
            }
        }


        /// <summary>
        /// 执行有参数的sql语句
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <param name="values">参数</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteCommand(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.Parameters.AddRange(values);
                conn.Open();
                int num = Convert.ToInt32(cmd.ExecuteNonQuery());
                conn.Close();
                return num;
            }
        }
        /// <summary>
        /// 执行无参数的sql语句，返回首行首列
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <returns>返回首行首列</returns>
        public static object GetScalar(string sql)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                conn.Open();
                object obj = cmd.ExecuteScalar();
                conn.Close();
                return obj;
            }
        }
        /// <summary>
        /// 执行有参数的sql语句,返回首行首列
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <param name="values">参数,是否返回首行首列</param>
        /// <returns>返回首行首列</returns>
        public static object ExecuteScalar(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.Parameters.AddRange(values);
                conn.Open();
                object obj = cmd.ExecuteScalar();
                conn.Close();
                return obj;
            }
        }

        /// <summary>
        /// 带事务的执行多条sql语句
        /// </summary>
        /// <param name="sqls"></param>    
        /// <returns></returns>
        //public static bool ExecuteCommandByTran(params ExecuteSql[] sqls)
        //{

        //    using (SqlConnection conn = new SqlConnection(Connstr))
        //    {
        //        conn.Open();
        //        //为数据库连接打开事务
        //        SqlTransaction tran = conn.BeginTransaction();
        //        SqlCommand cmd = new SqlCommand();
        //        cmd.Connection = conn;
        //        //为命令对象指定要应用事务
        //        cmd.Transaction = tran;
        //        try
        //        {

        //            for (int i = 0; i < sqls.Length; i++)
        //            {
        //                cmd.CommandText = sqls[i].SqlString;
        //                cmd.Parameters.AddRange(sqls[i].Pars);
        //                cmd.ExecuteNonQuery();
        //            }

        //            //没有异常的情况下，提交事务
        //            tran.Commit();

        //            return true;
        //        }
        //        catch (Exception ex)
        //        {
        //            //事务滚回去
        //            tran.Rollback();

        //            return false;

        //        }
        //        finally
        //        {

        //            conn.Close();
        //        }

        //    }
        //}

        #endregion

        #region 存储过程部分
        /// <summary>
        /// 执行sql语句返回DataTable
        /// </summary>
        /// <param name="sql">安全的sql语句</param>
        /// <returns>根据sql语句得到所有记录</returns>
        public static DataTable GetDataTableByProcedure(string sql)
        {

            using (SqlConnection conn = new SqlConnection(Connstr))
            {

                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.CommandType = CommandType.StoredProcedure;
                conn.Open();
                SqlDataAdapter sda = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                sda.Fill(dt);
                conn.Close();
                return dt;


            }


        }
        /// <summary>
        /// 执行带参数的sql语句返回DataTable
        /// </summary>
        /// <param name="sql">带参数的sql语句</param>
        /// <param name="values">参数</param>
        /// <returns>根据sql语句得到所有记录</returns>
        public static DataTable GetDataTableByProcedure(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                //指定查询的方式使用存储过程
                cmd.CommandType = CommandType.StoredProcedure;
                conn.Open();
                cmd.Parameters.AddRange(values);
                SqlDataAdapter sda = new SqlDataAdapter(cmd);
                DataTable dt = new DataTable();
                sda.Fill(dt);
                conn.Close();
                return dt;
            }


        }


        /// <summary>
        /// 执行无参数的sql语句
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteCommandByProcedure(string sql)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.CommandType = CommandType.StoredProcedure;
                conn.Open();
                int num = cmd.ExecuteNonQuery();
                conn.Close();
                return num;
            }
        }


        /// <summary>
        /// 执行有参数的sql语句
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <param name="values">参数</param>
        /// <returns>影响的行数</returns>
        public static int ExecuteCommandByProcedure(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddRange(values);
                conn.Open();
                int num = cmd.ExecuteNonQuery();
                conn.Close();
                return num;
            }
        }
        /// <summary>
        /// 执行无参数的sql语句，返回首行首列
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <returns>返回首行首列</returns>
        public static object GetScalarByProcedure(string sql)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.CommandType = CommandType.StoredProcedure;
                conn.Open();
                object obj = cmd.ExecuteScalar();
                conn.Close();
                return obj;
            }
        }
        /// <summary>
        /// 执行有参数的sql语句,返回首行首列
        /// </summary>
        /// <param name="sql">sql语句</param>
        /// <param name="values">参数,是否返回首行首列</param>
        /// <returns>返回首行首列</returns>
        public static object ExecuteScalarByProcedure(string sql, params SqlParameter[] values)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddRange(values);
                conn.Open();
                object obj = cmd.ExecuteScalar();
                conn.Close();
                return obj;
            }
        }
        #endregion
        
        #region 帮助方法
        //判断是否为主键
        public static bool IsPrimaryKey(String columnName, String tableName)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                conn.Open();
                SqlParameter[] parameters = new SqlParameter[3];
                parameters[0] = new SqlParameter("@table_name", tableName);
                parameters[1] = new SqlParameter("@table_owner", null);
                parameters[2] = new SqlParameter("@table_qualifier", null);
                SqlCommand comm = new SqlCommand();
                //指定存储过程名称
                comm.CommandText = "sp_pkeys";
                comm.Connection = conn;
                //声明执行命令的类型
                comm.CommandType = CommandType.StoredProcedure;
                comm.Parameters.AddRange(parameters);
                SqlDataAdapter ad = new SqlDataAdapter(comm);
                DataTable dt = new DataTable();
                ad.Fill(dt);
                DataRowCollection drc = dt.Rows;
                if (drc.Count == 0 || (drc[0]["COLUMN_NAME"].ToString().ToLower() != columnName.ToLower()))
                    return false;
                else
                    return true;
            }

        }
        //判断是否为外键
        public static bool IsForeignKey(String columnName, String tableName)
        {
            using (SqlConnection conn = new SqlConnection(Connstr))
            {
                conn.Open();
                SqlParameter[] parameters = new SqlParameter[3];
                parameters[0] = new SqlParameter("@pktable_name", tableName);
                parameters[1] = new SqlParameter("@pktable_owner", null);
                parameters[2] = new SqlParameter("@pktable_qualifier", null);
                SqlCommand comm = new SqlCommand();
                //指定存储过程名称
                comm.CommandText = "sp_fkeys";
                comm.Connection = conn;
                //声明执行命令的类型
                comm.CommandType = CommandType.StoredProcedure;
                comm.Parameters.AddRange(parameters);
                SqlDataAdapter ad = new SqlDataAdapter(comm);
                DataTable dt = new DataTable();
                ad.Fill(dt);
                DataRowCollection drc = dt.Rows;
                if (drc.Count == 0 || (drc[0]["COLUMN_NAME"].ToString().ToLower() != columnName.ToLower()))
                    return false;
                else
                    return true;
            }

        }
        #endregion
    }
}

2BaseDAL定义了一些主要的增删改查的方法因为只是开始做 所以只能是对单张表的操作

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Reflection;
using Model;

namespace DAL
{
    public abstract class BassDAL<T> where T : new()
    {
        //单表查询
        public virtual List<T> GetAllModels()
        {
            List<T> tList = new List<T>();
            string name = new T().GetType().Name;
            string sqlStr = "select * from " + name;
            DataTable dt = DBHelper.GetDataTable(sqlStr);

            foreach (DataRow dr in dt.Rows)
            {
                T t = new T();
                PropertyInfo[] proList = t.GetType().GetProperties();
                foreach (PropertyInfo pi in proList)
                {
                    string piName = pi.Name;
                    if (dt.Columns.Contains(piName))
                    {
                        if (!pi.CanWrite) continue;
                        object value = dr[piName];
                        if (value != DBNull.Value)
                            pi.SetValue(t, value, null);
                    }
                }
                tList.Add(t);
            }
            return tList;
        }
        //添加
        public virtual bool AddModel(T model)
        {
            PropertyInfo[] proList = model.GetType().GetProperties();
            string name = model.GetType().Name;
            string sqlStr = "insert into " + name;
            string filed = "(";
            string values = " values (";
            foreach (PropertyInfo pi in proList)
            {
                filed += pi.Name + ",";
                values += "'" + pi.GetValue(model, null).ToString() + "',";
            }
            filed = filed.Substring(0, filed.Length - 1) + ")";
            values = values.Substring(0, values.Length - 1) + ")";
            sqlStr = sqlStr + filed + values;
            return DBHelper.ExecuteCommand(sqlStr) != 0 ? true : false;
        }
        //修改
        public virtual bool UpdateModel(T model)
        {
            PropertyInfo[] proList = model.GetType().GetProperties();
            string name = model.GetType().Name;
            string sqlStr = "update " + name + " set ";
            foreach (PropertyInfo pi in proList)
            {
                if (pi.GetValue(model, null) != null && DBHelper.IsPrimaryKey(pi.Name, name) == false)
                {
                    sqlStr += pi.Name + "='" + pi.GetValue(model, null).ToString() + "',";
                }
            }
            sqlStr = sqlStr.Substring(0, sqlStr.Length - 1);
            foreach (PropertyInfo pi in proList)
            {
                if (pi.GetValue(model, null) != null && DBHelper.IsPrimaryKey(pi.Name, name) != false)
                {
                    sqlStr += " where " + pi.Name + "='" + pi.GetValue(model, null).ToString() + "'";
                }
            }
            return DBHelper.ExecuteCommand(sqlStr) != 0 ? true : false;
        }
        //删除
        public virtual bool DeleteModel(T model)
        {
            PropertyInfo[] proList = model.GetType().GetProperties();
            string name = model.GetType().Name;
            string sqlStr = "delete " + name + " where ";
            foreach (PropertyInfo pi in proList)
            {
                if (pi.GetValue(model, null) != null)
                {
                    if (DBHelper.IsPrimaryKey(pi.Name, name) != false)
                    {
                        sqlStr += pi.Name + "='" + pi.GetValue(model, null).ToString()+"'";
                    }
                }
            }
            return DBHelper.ExecuteCommand(sqlStr) != 0 ? true : false;
        }
    }
}

3使用BaseDAL

用实体类的DAL继承BaseDAL由于BaseDAL是一个泛型类所以要在继承的时候传入实体类即BassDAL<PetInfo>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Model;

namespace DAL
{
    public class Pet:BassDAL<PetInfo>
    {
    }
}

4这样就可以使用了

using System;
using System.Collections;
using System.Configuration;
using System.Data;

using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;

using DAL;
using Model;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        PetInfo petinfo = new PetInfo
        {
             Id = 1,
        };
        new Pet().DeleteModel(petinfo);
        this.GridView1.DataSource = new Pet().GetAllModels();
        this.GridView1.DataBind();
        
    }
}

有什么不足希望大家指出来，一起完善哈