DAL 数据链路层 非查询/查询

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data;
using System.Data.SqlClient;

namespace DAL
{
public class sqlHelper //非查询
{

public static int baba(string sql,List<SqlParameter>paras)

{

SqlConnection conn = new SqlConnection("server=.;database=schoolido;uid=sa;pwd=123");
conn.Open();
SqlCommand cmd = new SqlCommand(sql, conn);
cmd.Parameters.AddRange(paras.ToArray());
return cmd.ExecuteNonQuery();

}

}
}

public static DataTable name(string sql, List<SqlParameter> arr)
{
DataSet set = new DataSet();
SqlConnection conn = new SqlConnection(); //查询一批值
conn.Open();
SqlCommand dx = new SqlCommand(sql, conn);
dx.Parameters.AddRange(arr.ToArray());
SqlDataAdapter haha = new SqlDataAdapter(dx);
haha.Fill(set);
return set.Tables[0];

}
public static object name(string sql, List<SqlParameter> arr)
{

SqlConnection conn = new SqlConnection("");
SqlCommand dx = new SqlCommand(sql,conn); //查询一个值
dx.Parameters.Add(arr.ToArray());
return dx.ExecuteScalar();

}