连接ACCESS库,根据连接SQL的代码改,但错了
这是连接SQL的代码:
string sqlstring="select 部门,平均薪资=avg(目前薪资) from " + "章立民工作室 group by 部门";
SqlConnection MyConnection=new SqlConnection("server=NNLL;database=北风贸易;user=sa;password=nnll");
SqlCommand MyCommand=new SqlCommand(sqlstring,MyConnection);
MyConnection.Open();
SqlDataReader dr=MyCommand.ExecuteReader();
我要连接的是ACCESS,改成这个,用了两个参数:
//连接字串
string Provider="Provider=Microsoft.Jet.OLEDB.4.0";
string Database="Data Source=presell.mdb";
OleDbConnection MyConn=new OleDbConnection(Provider + ";" + Database);
string MySql="select Sid from users where Sna='@Sna' and Spa='@Spa'";
OleDbCommand MyCom=new OleDbCommand(MySql,MyConn);
//添加参数
MyCom.Parameters.Add("@Sna",System.Data.OleDb.OleDbType.Char,10).Value=Sna;
MyCom.Parameters.Add("@Spa",System.Data.OleDb.OleDbType.Char,10).Value=Spa;
MyConn.Open();
OleDbDataReader MyRd=MyCom.ExecuteReader(); //就这出错说是MyRd是未定义的值