Search code examples
c#tostringdatareader

Difference between (string)reader[0] and reader[0].ToString()

Is there a difference between DataReader[0].ToString() and (string)DataReader[0]?

My guess is that (string)DataReader[0] might fail if the database type isn't a string type, where DataReader[0].ToString() would just convert anything outside of a DB null to a string. Is that the case?

Which would be faster?

Solution

  • Those both introduce you to potential data exceptions, IMO the optimal way to read from a reader is:

    var x = reader[0] as string

    Then for numbers / bools etc I always use nullable types so you can get

    var y = reader[1] as int?

    Now if you absolutely are as opposed to nullables for some reason (I think they're great for knowing whether something is or not set)

    int i = (reader[1] as int?).GetValueOrDefault()