Data Types

sophia · September 26th, 2010, 08:55 AM

Hi Imar,
I am trying to get the values of data type smallint and bigint in the Business Logic Layer using the following code,

Code:

Using myReader As SqlDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection)
                    If myReader.Read() Then
                        Dim test As Short = myReader.GetShort(myReader.GetOrdinal("CategoryId"))
                        theProduct = New Product(myReader.GetLong(myReader.GetOrdinal("Id")), myReader.GetShort(myReader.GetOrdinal("CategoryId")))
                        theProduct.Name = myReader.GetString(myReader.GetOrdinal("Name"))

rest code goes hereâ¦â¦..
                    
                End Using

But problem is that I do not see any method GetShort & GetLong for the smallint and bigint data types respectively.
So is there any other method to cast these two variables in their respected types?

Thanks.

Imar · September 26th, 2010, 09:00 AM

Shorts and Longs are language specific aliases for the System.Int16 and System.Int64 types.... You'll find Get* methods for these on the SqlDataReader.

Imar

sophia · September 26th, 2010, 09:04 AM

Thanks Imar...

sophia · September 30th, 2010, 08:02 AM

Hi,
I am not getting any such Get methods which refer to Shorts & Longs.

Code:

Using myReader As SqlDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection)
                    If myReader.Read() Then
                        Dim test As Short = myReader.GetShort(myReader.GetOrdinal("CategoryId"))
                        theProduct = New Product(myReader.GetLong(myReader.GetOrdinal("Id")), myReader.GetShort(myReader.GetOrdinal("CategoryId")))
                        theProduct.Name = myReader.GetString(myReader.GetOrdinal("Name"))

rest code goes hereâ¦â¦..
                    
                End Using

What are these 2 methods?

Imar · September 30th, 2010, 08:18 AM

Isn't that in my previous answer???

Quote:

Shorts and Longs are language specific aliases for the System.Int16 and System.Int64 types.... You'll find Get* methods for these on the SqlDataReader.

Imar

sophia · October 1st, 2010, 09:09 AM

Hi Imar,
This time I am not getting you. What do you mean by Get*? If you are saying GetInt32, GetByte, GetString etc. collectively as Get* then I do not see any Get method for Shorts & Longs.
What are the exact methods for referencing the two (Shorts & Longs)?

Imar · October 1st, 2010, 12:43 PM

I am not sure why you don't get this and what's not clear in my previous posts, so I'll be as specirfic as possible:

Quote:

Shorts and Longs are language specific aliases for the System.Int16 and System.Int64 types

In other words, Shorts and Longs only exist in VB; they don't exist in .NET. In .NET their equivalents are System.Int16 and System.Int64.
The DataReader is a .NET type, so it's not aware of language specific types such as long. Instead, it's designed to work with System.Int16 and System.Int64 types. So, what happens when you look at the list of methods supported by the DataReader and see if you can find a GetInt16 or a GetInt64?

Imar

rakeshswain1986 · October 2nd, 2010, 03:10 AM

there is how many datatype c# support..?

Imar · October 2nd, 2010, 09:23 AM

Enough? 42 maybe? I don't know as I don't understand the question.

Did you figure out how to read longs and shorts?

Imar