c# - Datareader.HasRow is wrong -


can confirm or dispute problem i'm having accessing accdb database datareader. setup datareader , query database. when check datareader.hasrows, true, no matter if records present or not.

i've double verified data table empty, no records @ all, datareader.hasrows still says got records.

if go on , try datareader.read, when know there no records returned, error saying "no data exists row/column." expected.

has seen before? or can doesn't happen?

thanks

sql = @"select a.license, a.classid, a.currentlyin, a.totalscans " +     @"from attendance " +     @"where a.license = " + myscan.licenseint +         @" , a.classid = " + myscan.classid + ";"; _parent.statusoutput(sql);  cmddb = new oledbcommand(sql, cndb); try {     //cndb.open();      drdb = cmddb.executereader();     if (drdb.hasrows)     {         _parent.statusoutput("data reader has no rows");     }     else     {         _parent.statusoutput("data reader has rows.");         drdb.read();         _parent.statusoutput(drdb["license"].tostring() + ", " + drdb["classid"].tostring());     }

there go. sorry confusion on how post this.

in sample code here if reader has rows prints error

and if reader not have rows prints has , reads , throws exception

swap:

if (drdb.hasrows)         {             _parent.statusoutput("data reader has rows.");             drdb.read();             _parent.statusoutput(drdb["license"].tostring() + ", " + drdb["classid"].tostring());                     }         else         {             _parent.statusoutput("data reader has no rows");          }

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