How to achieve the C# 'as' keyword for value types in vb.net?

Question

Most of our development is done in vb.net (not my choice) and one frequently used code pattern uses an \'On Error GoTo\' followed by a \'Resume Next\' so that all database f

Answer 1

I don't think that VB.NET has any operator that mimics the functioning of the ?? operator of C#. However, you could use the equivalent of C#'s ternary operator - The IIF function in your case:

Admittedly ugly:

oObject.Name = IIf(oReader.Item("Name").Equals(DBNull.Value), DirectCast(oReader.Item("Name"), String), String.Empty)
oObject.Value = IIf(oReader.Item("Value").Equals(DBNull.Value), DirectCast(oReader.Item("Value"), Integer), -1)

Please make sure to read Stephen Weatherford's post in the link I provided above which suggests a generic IIf function that infers type requirements from the provided arguments. This becomes necessary because the IIf function always returns an Object!

A better option would be to create a function that performs this cast conditionally, rather than trying to do it in one line.