DataHelper

 1.建一个通用的处理数据的类

using  System;
using  System.Data;
using  System.Data.SqlClient;
using  System.Text;
namespace  Document
{
    /**//// <summary>
    /// Summary description for DataHelper.
    /// </summary>
    public class DataHelper
    {
        public DataHelper()
        {
            //
            // TODO: Add constructor logic here
            //
        }
        public static string ConnectionString=System.Configuration.ConfigurationSettings.AppSettings["ConnectionString"];
    
        GetDataSet#region GetDataSet
        public static DataSet GetDataSet(string sql)
        {
            SqlDataAdapter    sda =new SqlDataAdapter(sql,ConnectionString);
            DataSet ds=new DataSet();
            sda.Fill(ds);
            return ds;
        }
        #endregion

        ExecCommand#region ExecCommand
        public static int ExecCommand(SqlCommand sqlcom)
        {
            SqlConnection conn=new SqlConnection(ConnectionString);
            sqlcom.Connection =conn;
            conn.Open();
            try
            {
                int rtn=sqlcom.ExecuteNonQuery();
                return rtn;
            }
            catch(Exception ex) 
            {
                throw ex;                
            }
            finally
            {
                conn.Close();
            }
            return 0;

        }
        public static int ExecCommand(string sql)
        {
            if (sql.EndsWith(",")) sql=sql.Substring(0,sql.Length-1);
        
            SqlCommand sqlcom=new SqlCommand(sql);
            return ExecCommand(sqlcom);                
        }
        #endregion
        
        ExecuteScalar#region ExecuteScalar
        public static object ExecuteScalar(string sql)
        {
            SqlConnection conn=new SqlConnection(ConnectionString);
            SqlCommand sqlcom=new SqlCommand(sql,conn);
            conn.Open();
            try
            {
                object rtn=sqlcom.ExecuteScalar ();
                return rtn;
            }
            catch(Exception ex) 
            {
                throw ex;                
            }
            finally
            {
                conn.Close();
            }
            return null;
        }
        #endregion

        ExecSPCommand#region ExecSPCommand
        public static void ExecSPCommand(string sql,System.Data.IDataParameter[] paramers)
        {
            SqlConnection conn=new SqlConnection(ConnectionString);
            SqlCommand sqlcom=new SqlCommand(sql,conn);
            sqlcom.CommandType= CommandType.StoredProcedure ;

            foreach(System.Data.IDataParameter paramer in paramers)
            {
                sqlcom.Parameters.Add(paramer);
            }            
            conn.Open();
            try
            {
                sqlcom.ExecuteNonQuery();
            }
            catch(Exception ex) 
            {
                string s=ex.Message ;
            }
            finally
            {
                conn.Close();
            }
        }
        #endregion

        ExecSPDataSet#region ExecSPDataSet
        public static DataSet ExecSPDataSet(string sql,System.Data.IDataParameter[] paramers)
        {
            SqlConnection conn=new SqlConnection(ConnectionString);
            SqlCommand sqlcom=new SqlCommand(sql,conn);
            sqlcom.CommandType= CommandType.StoredProcedure ;

            foreach(System.Data.IDataParameter paramer in paramers)
            {
                sqlcom.Parameters.Add(paramer);
            }            
            conn.Open();
            
            SqlDataAdapter da=new SqlDataAdapter();
            da.SelectCommand=sqlcom;
            DataSet ds=new DataSet();
            da.Fill(ds);
        
            conn.Close();
            return ds;
        }

        #endregion

        DbType#region DbType
        private static System.Data.DbType GetDbType(Type type)
        {
            DbType result = DbType.String;
            if( type.Equals(typeof(int)) ||  type.IsEnum)
                result = DbType.Int32;
            else if( type.Equals(typeof(long)))