public class SqlHlper
    {
        public static readonly string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
        //执行增删改
        public static object ExecuteNonQuery(string sql, params SqlParameter[] pms)//SqlParameter需要调用Data.SqlClient
        {
            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();
                }
            }
        }
        //获取单个数据
        public static object ExecteScalar(string sql, params SqlParameter[] pms)
        {
            object obj = null;
            using (SqlConnection conn = new SqlConnection(constr))
            {
                SqlCommand cmd = new SqlCommand(sql, conn);
                conn.Open();
                if (pms != null)
                {
                    cmd.Parameters.AddRange(pms);
                }
                obj = cmd.ExecuteScalar();
            }
            return obj;
        }
        //获取多个数据
        public static SqlDataReader GetDataReader(string sql, params SqlParameter[] sps)
        {
            SqlConnection conn = new SqlConnection(constr);
            using (SqlCommand cmd = new SqlCommand(sql, conn))
            {
                if (sps != null)
                {
                    cmd.Parameters.AddRange(sps);
                }
                conn.Open();
                return cmd.ExecuteReader(CommandBehavior.CloseConnection);
            }
        }
        //查询多条数据
        public static DataTable GetDataTable(string sql, params SqlParameter[] sps)
        {
            DataTable dt = new DataTable();
            using (SqlDataAdapter da = new SqlDataAdapter(sql, constr))
            {
                if (sps != null)
                {
                    da.SelectCommand.Parameters.AddRange(sps);
                }
                da.Fill(dt);
            }
            return dt;
        }
    }