SQLhelper文档

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

namespace progressdemo.DAL
{
    public static  class SQLHelper
    {
        //获得配置文件中的连接字符串
        private static readonly string constr = ConfigurationManager.ConnectionStrings["sql"].ConnectionString;
        /// <summary>
        /// 执行insert、delete、update的方法
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="pms"></param>
        /// <returns></returns>
        public static int ExecteNonQuery(string sql, params SqlParameter[] pms)
        {
            //sqlconnection 表示连接数据库
            using (SqlConnection con=new SqlConnection(constr))
            {
                using (SqlCommand cmd=new SqlCommand(sql,con))
                {
                    if (pms!=null)
                    {
                        cmd.Parameters.AddRange(pms);
                    }
                    con.Open();
                    return cmd.ExecuteNonQuery();
                }
            }
        }
        /// <summary>
        /// 返回首行首列
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="pms"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sql,params SqlParameter[] pms)
        {
            using (SqlConnection con=new SqlConnection(constr))
            {
                using (SqlCommand cmd=new SqlCommand(sql,con))
                {
                    if (pms!=null)
                    {
                        cmd.Parameters.AddRange(pms);
                    }
                    con.Open();
                    return cmd.ExecuteScalar();
                }
            }
        }
        public static SqlDataReader ExecuteReader(string sql, params SqlParameter[] pms)
        {
            SqlConnection con=new SqlConnection(constr);
             try
             {
            using (SqlCommand cmd=new SqlCommand(sql,con))
            {
                if (pms != null)
                {
                    cmd.Parameters.AddRange(pms);
                }
                con.Open();
                //当调用ExecuteReader的时候如果传递的CommandBehavior.CloseConnection参数当reader关闭的时候
                //sqlconnection也被关闭
                SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                return reader;
            }
            }catch{
              if(con!=null){
                 con.Close();con.Disponse();
               }
               throw;
            }
        }
        public static DataTable ExecuteDataTable(string sql, params SqlParameter[] pms)
        {
            SqlDataAdapter sqlAdaper = new SqlDataAdapter(sql, constr);
            if (pms!=null)
            {
                sqlAdaper.SelectCommand.Parameters.AddRange(pms);
            }
            DataTable dt = new DataTable();
            sqlAdaper.Fill(dt);
            return dt;
        }
    }

}