Visual Basic 2005 Language Features Sample

  • Article

This sample demonstrates new language features in Visual Basic, including generics, operator overloading, and the Using keyword.

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Security noteSecurity Note:

This sample code is intended to illustrate a concept, and it shows only the code that is relevant to that concept. It may not meet the security requirements for a specific environment, and it should not be used exactly as shown. We recommend that you add security and error-handling code to make your projects more secure and robust. Microsoft provides this sample code "AS IS" with no warranties.

To run this sample

  • Press F5.

Demonstrates

This sample demonstrates these language features:

  • Operator overloading   The ValidatedString class represents a string with custom validation. The & operator returns the concatenation of two ValidatedString objects.

  • Generics   The Pair class holds two values. When you declare an instance of the Pair class, you specify the types of the two values. The Match method tests to whether the pair types and values are the same.

  • Using   The Using Statement (Visual Basic) references a stream resource opened by a request from a Web client. The stream instance is disposed of automatically at the end of the Using block.

  • TryCast and IsNot   TryCast attempts to cast an object to a particular type and returns the converted value. If the cast fails then Nothing is returned. The IsNot operator is used to test the return result for Nothing.

See Also

Concepts

Generic Types in Visual Basic

Reference

Operator Statement

Using Statement (Visual Basic)

Other Resources

Visual Basic Language Samples