Why Datareader cannot be initialized?

Question

we use abstract keyword before classname to restric creating the instance of a class. But datareader is not an abstract class,but we cant create instance of that..can you explain why? I searched about it then I found it does not have constructor that's why we cannot create object but as per my knowledge if there is no constructor then compiler automatic create a default constructor. Please help...

Accepted Answer

`DbDataReader` is an abstract class. If you mean `SqlDataReader` instead, it has no public constructor, that's why you can't create an instance. It has only an `internal` constructor (ILSpy):

```
// System.Data.SqlClient.SqlDataReader
internal SqlDataReader(SqlCommand command, CommandBehavior behavior)
{
    // ...
}
```

From MSDN:

To create a `SqlDataReader`, you must call the `ExecuteReader` method of the SqlCommand object, instead of directly using a constructor.

In general it is a good idea to avoid instantiating a `DataReader` since it needs to be created via `SqlCommand.ExecuteReader` only.

Why Datareader cannot be initialized?

Solution

Problem