sqlserver批量更新

class DBHelper
{
//操作配置文件
Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
//先取一次，做为对比的基础
SqlConnection conn = new SqlConnection();
SqlCommand comm = new SqlCommand();
//链接数据库
public void Open()
{
conn = new SqlConnection(config.AppSettings.Settings["connstr"].Value);
conn.Open();
}
//断开连接
public void Close()
{
conn.Close();
}
//执行sql，并返回第一行第一列
public object ExecuteScalar(string sql)
{
comm.CommandText = sql;
comm.Connection = conn;
return comm.ExecuteScalar();
}
//执行sql，并返回执行结果
public DataTable GetResult(string sql)
{
SqlDataAdapter sda = new SqlDataAdapter(sql, conn);
DataTable dt = new DataTable();
sda.Fill(dt);
return dt;
}
//执行sql
public void ExecuteNonQuery(string sql)
{
comm.CommandText = sql;
comm.ExecuteNonQuery();
}
//批量更新
public void Update(DataTable dt, string tablename)
{
using (SqlBulkCopy sqlcopy = new SqlBulkCopy(conn))
{
sqlcopy.BulkCopyTimeout = 10000;
sqlcopy.DestinationTableName = tablename;
sqlcopy.WriteToServer(dt);
}
}
}