c# - Store Select Results In DataTable -

i querying sql server table , storing result in data table, needing pass values datatable parameter second query. results of query stored in second datatable. syntax can not right. have, have multiple compile errors. can assist me syntax , proper syntax?

sql.datatable datatable1 = new sql.datatable(); string constring = @"server=hometest;database=testing;integrated security=sspi;"; stringbuilder query = new stringbuilder(); sql.datatable datatablesupervisors = new sql.datatable(); query.append("select top 1 supervisorid activesupervisors");  using (sqlconnection cn = new sqlconnection(constring)) {     using (sqldataadapter da = new sqldataadapter(query.tostring(), cn))         da.fill(datatablesupervisors); }  foreach (datarow row in datatablesupervisors.rows) { using (sqlconnection conn = new sqlconnection("server=hometest;database=testing;integrated security=sspi;") {     sqlcommand command = new sqlcommand();     command.commandtext = "select * testdb supervisorid = @supid;";     command.parameters.add("@supid", sqldbtype.varchar);     command.parameters["@supid"].value = row.field<string>("projectid");     command.connection = conn;                         using (sqldataadapter dt1 = new sqldataadapter()         dt1.fill(datatable1); }    }