ASP.net C#笔记 (一)新建三层项目

1.新建一个解决方案

新建项目-其他项目类型-解决方案

2.新建一个空项目在里面新建三层 注意类库右键解决方案添加
DAL
BLL
Model

3.DAL中新建用于查询数据库的类 DBHelper

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

namespace DAL
{
    public class DBHelper
    {

        //连接字符串 这里把数据库连接字符串放到web.config中
        //注意：当前上下文中不存在名称“ConfigurationManager”  是DAL没有添加using System.Configuration;引用
        static string strConn = ConfigurationManager.ConnectionStrings["ApplicationServices"].ToString();



        #region 执行查询，返回DataTable对象-----------------------



        public static DataTable GetTable(string strSQL)
        {
            return GetTable(strSQL, null);
        }
        public static DataTable GetTable(string strSQL, SqlParameter[] pas)
        {
            return GetTable(strSQL, pas, CommandType.Text);
        }
        /// <summary>
        /// 执行查询，返回DataTable对象
        /// </summary>
        /// <param name="strSQL">sql语句</param>
        /// <param name="pas">参数数组</param>
        /// <param name="cmdtype">Command类型</param>
        /// <returns>DataTable对象</returns>
        public static DataTable GetTable(string strSQL, SqlParameter[] pas, CommandType cmdtype)
        {
            DataTable dt = new DataTable(); ;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                SqlDataAdapter da = new SqlDataAdapter(strSQL, conn);
                da.SelectCommand.CommandType = cmdtype;
                if (pas != null)
                {
                    da.SelectCommand.Parameters.AddRange(pas);
                }
                da.Fill(dt);
            }
            return dt;
        }



        #endregion




        #region 执行查询，返回DataSet对象-------------------------




        public static DataSet GetDataSet(string strSQL)
        {
            return GetDataSet(strSQL, null);
        }

        public static DataSet GetDataSet(string strSQL, SqlParameter[] pas)
        {
            return GetDataSet(strSQL, pas, CommandType.Text);
        }
        /// <summary>
        /// 执行查询，返回DataSet对象
        /// </summary>
        /// <param name="strSQL">sql语句</param>
        /// <param name="pas">参数数组</param>
        /// <param name="cmdtype">Command类型</param>
        /// <returns>DataSet对象</returns>
        public static DataSet GetDataSet(string strSQL, SqlParameter[] pas, CommandType cmdtype)
        {
            DataSet dt = new DataSet(); ;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                SqlDataAdapter da = new SqlDataAdapter(strSQL, conn);
                da.SelectCommand.CommandType = cmdtype;
                if (pas != null)
                {
                    da.SelectCommand.Parameters.AddRange(pas);
                }
                da.Fill(dt);
            }
            return dt;
        }
        #endregion





        #region 执行非查询存储过程和SQL语句-----------------------------




        public static int ExcuteProc(string ProcName)
        {
            return ExcuteSQL(ProcName, null, CommandType.StoredProcedure);
        }

        public static int ExcuteProc(string ProcName, SqlParameter[] pars)
        {
            return ExcuteSQL(ProcName, pars, CommandType.StoredProcedure);
        }

        public static int ExcuteSQL(string strSQL)
        {
            return ExcuteSQL(strSQL, null);
        }

        public static int ExcuteSQL(string strSQL, SqlParameter[] paras)
        {
            return ExcuteSQL(strSQL, paras, CommandType.Text);
        }

        /// 执行非查询存储过程和SQL语句
        /// 增、删、改
        /// </summary>
        /// <param name="strSQL">要执行的SQL语句</param>
        /// <param name="paras">参数列表，没有参数填入null</param>
        /// <param name="cmdType">Command类型</param>
        /// <returns>返回影响行数</returns>
        public static int ExcuteSQL(string strSQL, SqlParameter[] paras, CommandType cmdType)
        {
            int i = 0;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand(strSQL, conn);
                cmd.CommandType = cmdType;
                if (paras != null)
                {
                    cmd.Parameters.AddRange(paras);
                }
                conn.Open();
                i = cmd.ExecuteNonQuery();
                conn.Close();
            }
            return i;

        }


        #endregion








        #region 执行查询返回第一行，第一列---------------------------------




        public static int ExcuteScalarSQL(string strSQL)
        {
            return ExcuteScalarSQL(strSQL, null);
        }

        public static int ExcuteScalarSQL(string strSQL, SqlParameter[] paras)
        {
            return ExcuteScalarSQL(strSQL, paras, CommandType.Text);
        }
        public static int ExcuteScalarProc(string strSQL, SqlParameter[] paras)
        {
            return ExcuteScalarSQL(strSQL, paras, CommandType.StoredProcedure);
        }
        /// <summary>
        /// 执行SQL语句，返回第一行，第一列
        /// </summary>
        /// <param name="strSQL">要执行的SQL语句</param>
        /// <param name="paras">参数列表，没有参数填入null</param>
        /// <returns>返回影响行数</returns>
        public static int ExcuteScalarSQL(string strSQL, SqlParameter[] paras, CommandType cmdType)
        {
            int i = 0;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand(strSQL, conn);
                cmd.CommandType = cmdType;
                if (paras != null)
                {
                    cmd.Parameters.AddRange(paras);
                }
                conn.Open();
                i = Convert.ToInt32(cmd.ExecuteScalar());
                conn.Close();
            }
            return i;

        }


        #endregion









        #region 查询获取单个值------------------------------------




        /// <summary>
        /// 调用不带参数的存储过程获取单个值
        /// </summary>
        /// <param name="ProcName"></param>
        /// <returns></returns>
        public static object GetObjectByProc(string ProcName)
        {
            return GetObjectByProc(ProcName, null);
        }
        /// <summary>
        /// 调用带参数的存储过程获取单个值
        /// </summary>
        /// <param name="ProcName"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public static object GetObjectByProc(string ProcName, SqlParameter[] paras)
        {
            return GetObject(ProcName, paras, CommandType.StoredProcedure);
        }
        /// <summary>
        /// 根据sql语句获取单个值
        /// </summary>
        /// <param name="strSQL"></param>
        /// <returns></returns>
        public static object GetObject(string strSQL)
        {
            return GetObject(strSQL, null);
        }
        /// <summary>
        /// 根据sql语句 和 参数数组获取单个值
        /// </summary>
        /// <param name="strSQL"></param>
        /// <param name="paras"></param>
        /// <returns></returns>
        public static object GetObject(string strSQL, SqlParameter[] paras)
        {
            return GetObject(strSQL, paras, CommandType.Text);
        }

        /// <summary>
        /// 执行SQL语句，返回首行首列
        /// </summary>
        /// <param name="strSQL">要执行的SQL语句</param>
        /// <param name="paras">参数列表，没有参数填入null</param>
        /// <returns>返回的首行首列</returns>
        public static object GetObject(string strSQL, SqlParameter[] paras, CommandType cmdtype)
        {
            object o = null;
            using (SqlConnection conn = new SqlConnection(strConn))
            {
                SqlCommand cmd = new SqlCommand(strSQL, conn);
                cmd.CommandType = cmdtype;
                if (paras != null)
                {
                    cmd.Parameters.AddRange(paras);

                }

                conn.Open();
                o = cmd.ExecuteScalar();
                conn.Close();
            }
            return o;

        }



        #endregion





        #region 查询获取DataReader------------------------------------




        /// <summary>
        /// 调用不带参数的存储过程，返回DataReader对象
        /// </summary>
        /// <param name="procName">存储过程名称</param>
        /// <returns>DataReader对象</returns>
        public static SqlDataReader GetReaderByProc(string procName)
        {
            return GetReaderByProc(procName, null);
        }
        /// <summary>
        /// 调用带有参数的存储过程，返回DataReader对象
        /// </summary>
        /// <param name="procName">存储过程名</param>
        /// <param name="paras">参数数组</param>
        /// <returns>DataReader对象</returns>
        public static SqlDataReader GetReaderByProc(string procName, SqlParameter[] paras)
        {
            return GetReader(procName, paras, CommandType.StoredProcedure);
        }
        /// <summary>
        /// 根据sql语句返回DataReader对象
        /// </summary>
        /// <param name="strSQL">sql语句</param>
        /// <returns>DataReader对象</returns>
        public static SqlDataReader GetReader(string strSQL)
        {
            return GetReader(strSQL, null);
        }
        /// <summary>
        /// 根据sql语句和参数返回DataReader对象
        /// </summary>
        /// <param name="strSQL">sql语句</param>
        /// <param name="paras">参数数组</param>
        /// <returns>DataReader对象</returns>
        public static SqlDataReader GetReader(string strSQL, SqlParameter[] paras)
        {
            return GetReader(strSQL, paras, CommandType.Text);
        }
        /// <summary>
        /// 查询SQL语句获取DataReader
        /// </summary>
        /// <param name="strSQL">查询的SQL语句</param>
        /// <param name="paras">参数列表，没有参数填入null</param>
        /// <returns>查询到的DataReader（关闭该对象的时候，自动关闭连接）</returns>
        public static SqlDataReader GetReader(string strSQL, SqlParameter[] paras, CommandType cmdtype)
        {
            SqlDataReader sqldr = null;
            SqlConnection conn = new SqlConnection(strConn);
            SqlCommand cmd = new SqlCommand(strSQL, conn);
            cmd.CommandType = cmdtype;
            if (paras != null)
            {
                cmd.Parameters.AddRange(paras);
            }
            conn.Open();
            //CommandBehavior.CloseConnection的作用是如果关联的DataReader对象关闭，则连接自动关闭
            sqldr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            return sqldr;
        }



        #endregion




        #region 批量插入数据---------------------------------------------




        /// <summary>
        /// 往数据库中批量插入数据
        /// </summary>
        /// <param name="sourceDt">数据源表</param>
        /// <param name="targetTable">服务器上目标表</param>
        public static void BulkToDB(DataTable sourceDt, string targetTable)
        {
            SqlConnection conn = new SqlConnection(strConn);
            SqlBulkCopy bulkCopy = new SqlBulkCopy(conn);   //用其它源的数据有效批量加载sql server表中
            bulkCopy.DestinationTableName = targetTable;    //服务器上目标表的名称
            bulkCopy.BatchSize = sourceDt.Rows.Count;   //每一批次中的行数

            try
            {
                conn.Open();
                if (sourceDt != null && sourceDt.Rows.Count != 0)
                    bulkCopy.WriteToServer(sourceDt);   //将提供的数据源中的所有行复制到目标表中
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                conn.Close();
                if (bulkCopy != null)
                    bulkCopy.Close();
            }

        }

        #endregion


    }
}

2015-1-27 22:32:35

发现asp.net每个页面在创建的时候vs都会自动生成一个表单，有时候我们希望通过enter键来提交表单，因为用户为了方便经常这样做。在asp.net中可以设置任意一个按钮为enter键提交。设置方法是直接在表单里面加入这一句话<form id="form1" runat="server" defaultbutton="ImageButton2">这里的defaultbutton就是默认提交按钮

http://blog.sina.com.cn/s/blog_4acf507301011ds5.html

http://blog.csdn.net/sunbett/article/details/6496843

搜索关键字：asp.net textbox 按enter请求到后台代码

http://www.cnblogs.com/carekee/category/221206.html