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Visual Basic provides control structures that help you dispose of a resource or reduce the number of times you have to repeat an object reference.
Using...End Using Construction
The Using...End Using
construction establishes a statement block within which you make use of a resource such as a SQL connection. You can optionally acquire the resource with the Using
statement. When you exit the Using
block, Visual Basic automatically disposes of the resource so that it is available for other code to use. The resource must be local and disposable. For more information, see Using Statement.
With...End With Construction
The With...End With
construction lets you specify an object reference once and then run a series of statements that access its members. This can simplify your code and improve performance because Visual Basic does not have to re-establish the reference for each statement that accesses it. For more information, see With...End With Statement.