sqlhelper

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

namespace sqlHealpler
{
public static class SqlHealper
{
private static readonly string constr = ConfigurationManager.ConnectionStrings["sqlcon"].ConnectionString;
/// <summary>
/// 执行insert，delete，update的方法
/// </summary>
/// <param name="sql">请输入参数1，要执行的sql语句</param>
/// <param name="pms">sql语句中的参数</param>
/// <returns></returns>
public static int ExectueNonQuery(string sql, params SqlParameter[] pms)
{
using (SqlConnection con=new SqlConnection(constr))
{
using (SqlCommand cmd=new SqlCommand (sql,con))
{

if (pms!=null)//说明还传了参数
{
cmd.Parameters.AddRange(pms);//将参数（课能是数组）添加到cmd对象中
}
con.Open();
return cmd.ExecuteNonQuery();//返回执行返回的值

}
}

}

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)//说明还传了参数
{
cmd.Parameters.AddRange(pms);
}
con.Open();
return cmd.ExecuteScalar();

}
}
}
/// <summary>
/// 当返回dataReader的时候，connection不能关闭，DataReader不能关闭。
/// 3给command对象一个参数 SqlDataReader reader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
/// 这是 在关闭reader的时候就把 connection 关闭了 。
///
/// </summary>
/// <param name="sql"></param>
/// <param name="pms"></param>
/// <returns></returns>
public static SqlDataReader Executereader(sql,params SqlParameter[] par)
{
SqlConnection conn=new SqlConnection(constr);

using(SqlCommand cmd=new SqlCommand())
{
if(par!=null)
{
cmd.Parameters.AddRange(par);
}
conn.Open();
SqlDataReader reader=cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
return reader;
}

}

public static DataTable ExecuteDataTable(string sql, params SqlParameter[] pms)
{
SqlDataAdapter adapter=new SqlDataAdapter(sql,constr);
DataSet ds=new DataSet("MyStudents");

adapter.selectcommand.parameters.addrange(par);
adapter.Fill(ds);

return ds.Tables[0];
}
}
}