ADO.Net之初入江湖

// Use Easy5DB;
// CREATE TABLE tb_SelCustomer
//(
//   ID INT IDENTITY(1,1) PRIMARY KEY, /*ID,主键*/
//   Name varchar(20) NOT NULL, /*姓名*/
//   Sex char(1) default('0'), /*性别：0为男，1为女，默认为0*/
//   CustomerType char(1) default('0'), /*客户类型：0为普通用户，1为VIP用户，默认为0*/
//   Phone varchar(12), /*联系电话*/
//   Email varchar(50), /*电子邮件*/
//   ContactAddress varchar(200), /*联系地址*/
//   Lat float, /*所在位置维度，用于在地图显示*/
//   Lng float, /*所在位置经度，用于在地图显示*/
//   Postalcode varchar(10), /*邮政编码*/
//   Remark varchar(50) /*备注*/
//)
 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data.SqlClient;
using System.Data;

namespace StartUp
{
    class Program
    {
        static void Main(string[] args)
        {
            //TestExecuteNonQuery();
            //TestExecuteExcuteReader();
            //TestExecuteScalar();
            //TestBeginExecuteNonQuery();
            //TestSqlParamterExecuteNonQuery("测试客户1", "123456789123", "Test@163.com", "中国深圳南山区");
            TestExecuteScalarForGetInsertRowId();
        }

        #region Command 对象的普通操作

        private static void TestExecuteNonQuery()
        {
            string connStr = @"Data Source=.\SQLEXPRESS;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            using (SqlConnection connection = new SqlConnection(connStr))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        StringBuilder strSQL = new StringBuilder(); strSQL.Append("insert into tb_SelCustomer "); strSQL.Append("values("); strSQL.Append("'liuhao','0','0','13822223333','liuhaorain@163.com','广东省深圳市宝安区',12.234556,34.222234,'422900','备注信息')");

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSQL.ToString();

                        try
                        {
                            int rows = command.ExecuteNonQuery();
                            Console.WriteLine("影响行数：{0}", rows);
                            Console.ReadKey();
                        }
                        catch (Exception)
                        {
                            Console.WriteLine("执行命令失败");
                            Console.ReadKey();
                        }
                    }

                }
                catch (Exception)
                {
                    Console.WriteLine("打开数据库失败");
                    Console.ReadKey();
                }
            }
        }

        /// <summary>
        /// SqlDataReader sqlDataReader = command.ExecuteReader();基于连接
        /// for (int i = 0; i < sqlDataReader.FieldCount; i++)
        ///{
        ///    Console.WriteLine("{0}:{1}", sqlDataReader.GetName(i), sqlDataReader.GetValue(i));
        ///}
        ///
        ///看到用SqlDataReader不符合快速开发应用程序（RAD），
        ///完美的解决方案是用SqlDataAdapter
        /// </summary>
        private static void TestExecuteExcuteReader()
        {
            string connStr = @"Data Source=.\SQLEXPRESS;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            using (SqlConnection connection = new SqlConnection(connStr))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        StringBuilder strSQL = new StringBuilder();
                        strSQL.Append("select * from tb_SelCustomer");

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSQL.ToString();

                        try
                        {
                            SqlDataReader sqlDataReader = command.ExecuteReader();
                            while (sqlDataReader.Read())
                            {
                                for (int i = 0; i < sqlDataReader.FieldCount; i++)
                                {
                                    Console.WriteLine("{0}:{1}", sqlDataReader.GetName(i), sqlDataReader.GetValue(i));
                                }

                                Console.WriteLine("----------------------------");
                            }

                            Console.ReadKey();
                        }
                        catch (Exception)
                        {
                            Console.WriteLine("执行命令失败");
                            Console.ReadKey();
                        }
                    }

                }
                catch (Exception)
                {
                    Console.WriteLine("打开数据库失败");
                    Console.ReadKey();
                }
            }
        }

        private static void TestExecuteScalar()
        {
            string connStr = @"Data Source=.\SQLEXPRESS;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            using (SqlConnection connection = new SqlConnection(connStr))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        StringBuilder strSQL = new StringBuilder();
                        strSQL.Append("Select count(*) from tb_SelCustomer ");

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSQL.ToString();

                        try
                        {
                            int rows = (int)command.ExecuteScalar();
                            Console.WriteLine("执行ExcuteScalar方法：共{0}行记录", rows);
                            Console.ReadKey();
                        }
                        catch (Exception)
                        {
                            Console.WriteLine("执行命令失败");
                            Console.ReadKey();
                        }
                    }

                }
                catch (Exception)
                {
                    Console.WriteLine("打开数据库失败");
                    Console.ReadKey();
                }
            }
        }

        #endregion

        #region Command对象的异步操作

        private static void TestBeginExecuteNonQuery()
        {
            string connStr = @"Data Source=.\SQLEXPRESS;" +
                               "Initial Catalog=Easy5DB;" +
                               "User ID=sa;Password=123456;" +
                               "Asynchronous Processing=true"; //必须开启SqlConnection的异步查询
           
            using (SqlConnection connection = new SqlConnection(connStr))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        StringBuilder strSQL = new StringBuilder();
                        //插入测试客户
                        for (int i = 1; i <= 10; ++i)
                        {
                            strSQL.Append("insert into tb_SelCustomer ");
                            strSQL.Append("values('");
                            string name = "测试客户" + i.ToString();
                            strSQL.Append(name);
                            strSQL.Append("','0','0','13822223333','liuhaorain@163.com','广东省深圳市宝安区',12.234556,34.222234,'422900','备注信息'); ");
                        }

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSQL.ToString();

                        try
                        {
                            double time = 0.0;
                            IAsyncResult iar = command.BeginExecuteNonQuery();

                            //插入没有完成，在可以别的事情
                            while (!iar.IsCompleted)
                            {
                                System.Threading.Thread.Sleep(1);
                                ++time;
                                Console.WriteLine("已经插入{0}个", time);
                            }
                           
                            Console.WriteLine("完成", time);
                            Console.ReadKey();

                            command.EndExecuteNonQuery(iar);
                        }
                        catch (Exception)
                        {
                            Console.WriteLine("执行命令失败");
                            Console.ReadKey();
                        }
                    }

                }
                catch (Exception)
                {
                    Console.WriteLine("打开数据库失败");
                    Console.ReadKey();
                }
            }
        }

        #endregion

        /// <summary>
        /// 使用参数化查询
        /// </summary>
        /// <param name="name"></param>
        /// <param name="phone"></param>
        /// <param name="email"></param>
        /// <param name="address"></param>
        private static void TestSqlParamterExecuteNonQuery(string name,
            string phone,
            string email,
            string address)
        {
            string connStr = @"Data Source=.\SQLEXPRESS;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            using (SqlConnection connection = new SqlConnection(connStr))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        //参数化，避免SQL注入攻击
                        SqlParameter[] parameters = new SqlParameter[]
                        {
                            new SqlParameter("@Phone", SqlDbType.VarChar, 12),
                            new SqlParameter("@Email", SqlDbType.VarChar, 50),
                            new SqlParameter("@Address", SqlDbType.VarChar, 200),
                            new SqlParameter("@Name", SqlDbType.VarChar, 20),
                        };

                        parameters[0].Value = phone;
                        parameters[1].Value = email;
                        parameters[2].Value = address;
                        parameters[3].Value = name;

                        foreach (var item in parameters)
                        {
                            command.Parameters.Add(item);
                        }

                        StringBuilder strSQL = new StringBuilder();
                        strSQL.Append("Update tb_SelCustomer Set ");
                        strSQL.Append("Phone = @Phone,");
                        strSQL.Append("Email = @Email,");
                        strSQL.Append("ContactAddress = @Address ");
                        strSQL.Append("where Name = @Name;");

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSQL.ToString();

                        try
                        {
                            int rows = command.ExecuteNonQuery();
                            Console.WriteLine("影响行数：{0}", rows);
                            Console.ReadKey();
                        }
                        catch (Exception e)
                        {
                            Console.WriteLine("执行命令失败:" + e.Message);
                            Console.ReadKey();
                        }
                    }

                }
                catch (Exception)
                {
                    Console.WriteLine("打开数据库失败");
                    Console.ReadKey();
                }
            }
        }

        /// <summary>
        /// 用SQL Server数据库原生的OUTPUT关键字。
        ///
        /// OUTPUT关键字返回INSERT操作的一个字段（一般是主键ID）。
        ///
        /// 因此我们只要结合OUTPUT关键字以及ExecuteScalar方法，
        /// 就很容易得到插入行的主键。
        /// </summary>
        private static void TestExecuteScalarForGetInsertRowId()
        {
            string connectionString = @"Data Source=.\SQLEXPRESS;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            //string connectionString = @"Data Source=127.0.0.1;Initial Catalog=Easy5DB;User ID=sa;Password=123456";
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                try
                {
                    connection.Open();

                    using (SqlCommand command = new SqlCommand())
                    {
                        StringBuilder strSql = new StringBuilder();
                        strSql.Append("insert tb_SelCustomer(Name)");
                        strSql.Append("OUTPUT inserted.ID values(@Name)");

                        command.Connection = connection;
                        command.CommandType = CommandType.Text;
                        command.CommandText = strSql.ToString();

                        SqlParameter parmName = new SqlParameter("@Name", SqlDbType.VarChar, 20);
                        parmName.Value = "人才";
                        command.Parameters.Add(parmName);

                        try
                        {
                            int inserteId = (int)command.ExecuteScalar();
                            Console.WriteLine("InsetID:{0}", inserteId);
                            Console.ReadKey();
                        }
                        catch (Exception e)
                        {
                            Console.WriteLine("执行命令失败："+ e.Message);
                            Console.ReadKey();
                        }

                    }
                }
                catch (Exception e)
                {
                    Console.WriteLine("打开数据库失败："+ e.Message);
                }
            }
        }

        #region DataAdapter 和 DataSet
        /*1.DataAdapter:基于连接的
         * 它为外部数据源与本地DataSet集合架起了一座坚实的桥梁，
         * 将从外部数据源检索到的数据合理正确的调配到本地的DataSet集合中。
         *
         * •表或列名映射：维护本地DataSet表名和列名与外部数据源表名与列名的映射关系。
         * （不想SqlDataReader那样人工映射）

         *
         * 2.DataSet:基于非连接的
         * DataSet是基于非连接的（不需要连接数据库）
         */

        

        #endregion
    }
}