asp.net - System.IndexOutOfRangeException on SQLDataReader Value Using C# -

i have sqldatareader returns 3 integers. however, there occasions when 2 of integers return null values.

to round wrote following:

int shoppingcartheadid = 0; int billid = 0; int delid = 0;  conn.open(); reader = comm.executereader(); if (reader.read()) {        shoppingcartheadid = convert.toint32(reader["shoppingcartheadid"]);         if (!reader.isdbnull(billid))        {             billid = convert.toint32(reader["billid"]);        }         if (!reader.isdbnull(delid))        {             delid = convert.toint32(reader["delid"]);        }                 } reader.close(); 

unfortunately i'm still getting error message. suggestions?

ps tried no luck

if (reader["billid"] != null)

i try access index instead of column name, in case passing not existing column name.

also, make sure wrap reader using block in case if there exception reader closed , disposed, example in way:

... using(var reader = comm.executereader()) {     if (reader.read())     {            shoppingcartheadid = convert.toint32(reader[0]);             if (!reader.isdbnull(1))            {                 billid = convert.toint32(reader[1]);            }             if (!reader.isdbnull(2))            {                 delid = convert.toint32(reader[2]);            }     } }