c# - Input string was not in a correct format in SqlCommand -

here code used , popup exception @ 3rd command.commandtext assignment same way used in 2nd command.commandtext assignment,

  sqlcommand command = conn.createcommand();   conn.open();   //1st   command.commandtext = query;   sqldatareader reader = command.executereader();   arraylist almaingrid = new arraylist();    while (reader.read())    {       supporttable table = new supporttable();      table.laysheetno = reader.getvalue(0).tostring();      table.plnlaystarttime = reader.getdatetime(1).tostring();      table.plnlayendtime = reader.getvalue(2).tostring();      table.laytableid = reader.getvalue(3).tostring();// reader.getvalue(3).tostring();      table.layteamid = reader.getvalue(4).tostring();      almaingrid.add(table);    }    reader.close();     foreach (supporttable table in almaingrid)      {        //2nd        command.commandtext = string.format("select ctdesc cuttable ctid ={0}", int.parse(table.laytableid));       string tabledesc = (string)command.executescalar();       table.layteamid = tabledesc;       //3rd-in command.commandtext       command.commandtext = string.format("select teamdesc team teamid ={0}", int.parse(table.layteamid));       string teamdesc = (string)command.executescalar();       table.layteamid = teamdesc;      }      dgvmain.datasource = almaingrid; 

when assign table.layteamid in line couple of lines above seeing exception:

table.layteamid = tabledesc; 

i expect tabledesc assigning value table.layteamid cannot parsed int , blows when try parse here:

command.commandtext = string.format("select teamdesc team teamid ={0}", int.parse(table.layteamid)); 

note:

this bad way form queries concatenating strings. leave vulnerable sql injection attacks if aren't careful. use parameterized queries sanitize queries before execute them on database.