sqldbhelper

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

namespace Common
{
    public abstract class DbHelperSQL
    {
        //格式化字符串
        public static string inSQL(string formatStr)
        {
            string Str = formatStr;
            if (formatStr != null && formatStr != string.Empty)
            {
                Str = Str.Replace("'", "''");
            }
            return Str;
        }

        //获取连接字符串
        public static string ConnectionString
        {
            get 
            {
                string _connectionstring = ConfigurationManager.ConnectionStrings["ApplicationServices"].ConnectionString;
                string ConStringEncrypt = ConfigurationManager.AppSettings["ApplicationServices"];
                if (ConStringEncrypt =="true")
                {
                    _connectionstring = DESEncrypt.Encrypt(_connectionstring);
                }
                return _connectionstring;
            }
        }

        #region 执行带参数的SQL语句

        // 执行查询语句，返回SqlDataReader ( 注意：调用该方法后，一定要对SqlDataReader进行Close )
        public static  SqlDataReader ExecuteReader(string SQLString, params SqlParameter[] cmdParms)
        {
            SqlConnection connection = new SqlConnection(ConnectionString);
            SqlCommand cmd = new SqlCommand();
            try
            {
                PrepareCommand(cmd,connection,null,SQLString,cmdParms);
                SqlDataReader myReader=cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return myReader;
            }
            catch(System.Data.SqlClient.SqlException e)
            {
                throw e;
            }
        }

        // 执行SQL语句，返回影响的记录数
        public static int ExecuteSql(string SQLString, params SqlParameter[] cmdParms)
        {
            using (SqlConnection connection = new SqlConnection(ConnectionString))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    try
                    {
                        PrepareCommand(cmd,connection,null,SQLString,cmdParms);
                        int rows=cmd.ExecuteNonQuery();
                        cmd.Parameters.Clear();
                        return rows;
                    }
                    catch(System.Data.SqlClient.SqlException e)
                    {
                        throw e;
                    }
                }
            }
        }
        
        // 执行查询语句，返回DataSet
        private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, string cmdText, SqlParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;
            cmd.CommandType = CommandType.Text;
            if (cmdParms != null)
            {
                foreach (SqlParameter parameter in cmdParms)
                {
                    if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
                        (parameter.Value == null))
                    {
                        parameter.Value = DBNull.Value;
                    }
                    cmd.Parameters.Add(parameter);
                }
            }
        }

        #endregion
    }
}