It might sound kiddish or silly but i wanna know that in codes like..
SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
rdr.Read();
Response.Write(rdr[1]. ToString());
how do we use the SqlDataReader object as an array (rdr[1]) without declaration?
What I want to know is, what is happening in the following line?
Response.Write(rdr[1].ToString());
Since rdr is an object, how art we able to use square brackets with that?
You are looking for Indexers.
Please refer to this link.
Indexers are a syntactic convenience that enable you to create a class, struct, or interface that client applications can access just as an array
you can do something like this.
Object[] values = new Object[reader.FieldCount];
int fieldCount = reader.GetValues(values);
Console.WriteLine("reader.GetValues retrieved {0} columns.",
fieldCount);
for (int i = 0; i < fieldCount; i++)
Console.WriteLine(values[i]);
Console.WriteLine();
No, since SqlDataReader is a forward-only read-only stream of rows from a SQL Server database, the stream of rows will be looped through whether explicitly in your code or hidden in a framework implementation (such as DataTable's Load method). So you cannot directly convert it to array type. You need to convert it to list.
It sounds like using a generic list and then returning the list as an array would be a good option. For example,
List list = new List();
while (rdr.Read())
{
list.Add(rdr.GetInt32(0));
}
return list.ToArray();
