这看起来有什么问题？

private int DBUpdate(){

DAL dal = new DAL();
string upd = "UPDATE [RPform] SET [ProjectName] = '@pname', [ProjectCode] = '@pcode', [Country] = @cnt, ";
upd += "[StartDate] = '@startdate', [FinishDate] = '@finishdate', [TotalParticipants] = @totpart, [ArrivalDate] = '@arrivedate', ";
upd += "[AirportTransfer] = @airtran, [AirportDate] = '@airdate', [AirportHours] = @airhour, [AirportMinutes] = @airmin, ";
upd += "[Problems] = '@problems', [FirstDayActivities] = '@fdayact' ";
upd += "WHERE [UserID]=@usid";

    OleDbParameter[] parm = new OleDbParameter[] { 
    new OleDbParameter("@pname",projname.Text),
    new OleDbParameter("@pcode",projcode.Text),
    new OleDbParameter("@cnt",countries.SelectedIndex),
    new OleDbParameter("@startdate",datestart.Text),
    new OleDbParameter("@finishdate",datefinish.Text),
    new OleDbParameter("@totpart",totalparticipants.Text),
    new OleDbParameter("@arrivedate",datearrival.Text),
    new OleDbParameter("@airtran",RadioButtonList1.SelectedValue),
    new OleDbParameter("@airdate",dateairport.Text),
    new OleDbParameter("@airhour",airporthours.SelectedIndex),
    new OleDbParameter("@airmin",airportminutes.SelectedIndex),
    new OleDbParameter("@problems",problems.Value),
    new OleDbParameter("@fdayact",firstday.Value),
    new OleDbParameter("@usid",user.ID)
    };
 return (dal.UpdateRow(upd,false,parm));
}

///它不会导致异常,但会返回0行受影响.从MS Access中执行相同的查询时,它可以正常工作.因此,我认为这个问题与参数的处理有关......但是什么呢？谢谢

塞尔吉奥:这是否可以,明确设置OleDbTypes？

///whatever ...
        new OleDbParameter("@problems",problems.Value),
        new OleDbParameter("@fdayact",firstday.Value),
        new OleDbParameter("@usid",user.ID)
        };
//then telling each one what they will be ... 
        parm[0].OleDbType = OleDbType.VarWChar;
        parm[1].OleDbType = OleDbType.VarWChar;

///
     return (dal.UpdateRow(upd,false,parm));

Nelson Reis.. 6

检查是否正确设置了user.ID的值.

在您的upd命令字符串中,您使用引号包围参数,如下所示:

[StartDate] = '@startdate'

删除所有参数中的引号.

检查是否正确设置了user.ID的值.

在您的upd命令字符串中,您使用引号包围参数,如下所示:

[StartDate] = '@startdate'

删除所有参数中的引号.