private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
        {
            tr.Show();
            if (e.Node.Level==2)
            {

                string str = "select [Typeid] from　[OutcomeList] where [Typename]='" + e.Node.Text + "'";
                    // "')  union select Typeid  from OutcomeList  where (Typename='" + e.Node.Text+"');";
 //MessageBox.Show(str,"notes");
          
    
                tr.define(str);
            }
        }




  public void define(string s)
        {
          
          c = new Conn();
            OleDbCommand Comm = new OleDbCommand(s,c.createconn());
           MessageBox.Show(s, "notes");
        OleDbDataReader dr=Comm.ExecuteReader();
   while (dr.Read())
   {
       this.label1.Text = dr.GetString(0);
   }
   dr.Close();
   Comm.Connection.Close();
          
            
        }


    class Conn
    {
        public OleDbConnection createconn()
        {
        
                OleDbConnection conn = new OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=data.mdb");
                conn.Open();
                return conn;
         
       
        }

    }




可以连到数据库，在        OleDbDataReader dr=Comm.ExecuteReader();
出现异常 +        $exception    {"语法错误 (操作符丢失) 在查询表达式 '[Typeid] from　[OutcomeList] where [Typename]='食品'' 中。"}    System.Exception {System.Data.OleDb.OleDbException}


请帮帮我啊