SqlHelper 帮助类

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

namespace OA.Dal
{
    public class SqlHelper
    {
        public static readonly string ConnStr = "Data Source=.;Initial Catalog=myOffice;Persist Security Info=True;uid=sa;pwd=sa;Pooling=False";

        
        /// <summary>
        /// 为Command对象的执行做准备
        /// </summary>
        /// <param name="cmd">要执行的SqlCommand对象</param>
        /// <param name="conn">SqlConnection对象</param>
        /// <param name="trans">事物对象</param>
        /// <param name="cmdType">0表示Text,1表示StoredProcedure，2表示TableDirect</param>
        /// <param name="cmdText">要执行的Sql语句或存储过程名称</param>
        /// <param name="cmdParms">SqlParameter参数数组</param>
        
        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, int cmdType, string cmdText, SqlParameter[] cmdParms)
        {

            if (conn.State != ConnectionState.Open)
                conn.Open();

            cmd.Connection = conn;
            cmd.CommandText = cmdText;

            if (trans != null)
                cmd.Transaction = trans;
            switch (cmdType)
            {
                case 0:
                    cmd.CommandType = CommandType.Text;
                    break;
                case 1:
                    cmd.CommandType = CommandType.StoredProcedure;
                    break;
                case 2:
                    cmd.CommandType = CommandType.TableDirect;
                    break;
                default:
                    cmd.CommandType = CommandType.Text;
                    break;

            }
           

            if (cmdParms != null)
            {
                foreach (SqlParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }
        }

        /// <summary>
        /// 执行带参数的存储过程
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">0表示Text，1表示StoredProcedure，2表示TableDirect</param>
        /// <param name="cmdText">存储过程名称</param>
        /// <param name="commandParameters">SqlParameter参数数组</param>
        /// <returns>返回受影响的行数</returns>
        public static int ExecuteNonQuery(string connectionString, int cmdType, string cmdText, params SqlParameter[] commandParameters)
        {

            SqlCommand cmd = new SqlCommand();

            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }
        /// <summary>
        /// 执行没有返回结果集的SQL语句
        /// </summary>
        /// <param name="sql">要执行的SQL语句</param>
        /// <returns>受影响的行数</returns>
        public static int ExecuteNonQuery(string sql)
        {
            SqlCommand cmd = new SqlCommand();
            using (SqlConnection conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, conn, null, 0, sql, null);
                int val = cmd.ExecuteNonQuery();
                return val;
            }
        }
        /// <summary>
        /// 执行带参数的且没有返回结果集的SQL语句
        /// </summary>
        /// <param name="sql">要执行的SQL语句</param>
        /// <param name="commandParameters">SQL参数数组</param>
        /// <returns>受影响行数</returns>
        public static int ExecuteNonQuery(string sql, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            using (SqlConnection conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, conn, null, 0, sql, commandParameters); 
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }

      
        /// <summary>
        /// 执行未返回结果集的存储过程
        /// </summary>
        /// <param name="sql">存储过程名称</param>
        /// <param name="storedProcedure">0表示Text，1表示StoredProcedure，2表示TableDirect</param>
        /// <returns>受影响行数</returns>
        public static int ExecuteNonQuery(string sql,int storedProcedure)
        {
            SqlCommand cmd = new SqlCommand();
            using (SqlConnection conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, conn, null, storedProcedure, sql, null); 
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }
        /// <summary>
        /// 执行带参数的存储过程
        /// </summary>
        /// <param name="sql">存储过程名称</param>
        /// <param name="storedProcedure">0表示Text，1表示StoredProcedure，2表示TableDirect</param>
        /// <param name="commandParameters">存储过程参数数组</param>
        /// <returns>返回有影响行数</returns>
        public static int ExecuteNonQuery(string sql, int storedProcedure, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            using (SqlConnection conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, conn, null, storedProcedure, sql, commandParameters); 
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }
        /// <summary>
        /// 执行基于事物的带参数的SQL
        /// </summary>
        /// <param name="trans">SqlTransaction事物对象</param>
        /// <param name="cmdText">要执行的SQL语句</param>
        /// <param name="commandParameters">SQL语句参数</param>
        /// <returns>受影响的行数</returns>
        public static int ExecuteNonQuery(SqlTransaction trans, string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            PrepareCommand(cmd, trans.Connection, trans, 0, cmdText, commandParameters);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }
        /// <summary>
        /// 执行带参数的SQL语句返回一个SqlDataReader对象
        /// </summary>
        /// <param name="cmdText">要执行的SQL语句</param>
        /// <param name="commandParameters">SqlParameter参数数组</param>
        /// <returns>SqlDataReader对象</returns>
        public static SqlDataReader ExecuteReader(string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            SqlConnection conn = new SqlConnection(ConnStr);

            // we use a try/catch here because if the method throws an exception we want to 
            // close the connection throw code, because no datareader will exist, hence the 
            // commandBehaviour.CloseConnection will not work
            try
            {
                PrepareCommand(cmd, conn, null, 0, cmdText, commandParameters);
                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }
        /// <summary>
        /// 执行SQL语句返回一个SqlDataReader对象
        /// </summary>
        /// <param name="cmdText">要执行的Sql语句</param>
        /// <returns>SqlDataReader对象</returns>
        public static SqlDataReader ExecuteReader(string cmdText)
        {
            SqlCommand cmd = new SqlCommand();
            SqlConnection conn = new SqlConnection(ConnStr);
            try
            {
                PrepareCommand(cmd, conn, null, 0, cmdText, null);
                SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return rdr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }
        /// <summary>
        /// 执行带参数的SQL语句，返回首行首列的值
        /// </summary>
        /// <param name="cmdText">要执行的SQL语句</param>
        /// <param name="commandParameters">SqlParamter参数数组</param>
        /// <returns>首行首列的值</returns>
        public static object ExecuteScalar(string cmdText, params SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();

            using (SqlConnection connection = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, connection, null, 0, cmdText, commandParameters);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
        }
        /// <summary>
        /// 执行SQL语句，返回首行首列的值 
        /// </summary>
        /// <param name="cmdText">要执行的SQL语句</param>
        /// <returns>首行首列的值</returns>
        public static object ExecuteScalar(string cmdText)
        {
            SqlCommand cmd = new SqlCommand();

            using (SqlConnection connection = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, connection, null, 0, cmdText, null);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }
        }

        /// <summary>
        /// 执行SQL语句返回一个DataSet
        /// </summary>
        /// <param name="sql">要执行的SQL语句</param>
        /// <returns>DataSet对象</returns>
        public static DataSet ExecuteDataSet(string sql)
        {
            SqlCommand cmd = new SqlCommand();
            DataSet ds = new DataSet();
            using (SqlConnection Conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, Conn, null, 0, sql, null);
                SqlDataAdapter dapter = new SqlDataAdapter(cmd);
                dapter.Fill(ds);
                cmd.Parameters.Clear();
                return ds;
            }
        }
        /// <summary>
        /// 执行带参数的SQL语句返回一个DataSet
        /// </summary>
        /// <param name="sql">要执行的SQL语句</param>
        /// <param name="commandParameters">参数数组</param>
        /// <returns>DataSet对象</returns>
        public static DataSet ExecuteDataSet(string sql,SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            DataSet ds = new DataSet();
            using (SqlConnection Conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, Conn, null, 0, sql,commandParameters);
                SqlDataAdapter dapter = new SqlDataAdapter(cmd);
                dapter.Fill(ds);
                cmd.Parameters.Clear();
                return ds;
            }
        }

        /// <summary>
        /// 执行带参数的存储过程返回一个DataSet
        /// </summary>
        /// <param name="sql">存储过程名称</param>
        /// <param name="storedProcedure">0表示Text,1表示StoredProcedure，2表示TableDirect</param>
        /// <param name="commandParameters">存储过程参数</param>
        /// <returns>DataSet对象</returns>
        public static DataSet ExecuteDataSet(string sql, int storedProcedure,SqlParameter[] commandParameters)
        {
            SqlCommand cmd = new SqlCommand();
            DataSet ds = new DataSet();
            using (SqlConnection Conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, Conn, null, storedProcedure, sql, commandParameters);
                SqlDataAdapter dapter = new SqlDataAdapter(cmd);
                dapter.Fill(ds);
                cmd.Parameters.Clear();
                return ds;
            }
        }

        /// <summary>
        /// 执行带参数的存储过程返回一个DataSet
        /// </summary>
        /// <param name="sql">存储过程名称</param>
        /// <param name="storedProcedure">0表示Text,1表示StoredProcedure，2表示TableDirect</param>
        /// <returns>DataSet对象</returns>
        public static DataSet ExecuteDataSet(string sql, int storedProcedure)
        {
            SqlCommand cmd = new SqlCommand();
            DataSet ds = new DataSet();
            using (SqlConnection Conn = new SqlConnection(ConnStr))
            {
                PrepareCommand(cmd, Conn, null, storedProcedure, sql, null);
                SqlDataAdapter dapter = new SqlDataAdapter(cmd);
                dapter.Fill(ds);
                cmd.Parameters.Clear();
                return ds;
            }
        }
    }
}