Definition - What does Using Statement mean?
A using statement, in C#, is a statement that contains the "using" keyword and provides the syntax to specify the scope of the use of a resource object.
The using statement is useful for objects whose lifetimes are within the method or block in which they are created. This statement reduces the code in which resource-intensive operations are performed by providing simpler syntax and eliminating the need for multiple calls to release the resources at the end of their scope. Because it simplifies the code necessary for creating, cleaning up and handling an error while using the resource object, the using statement saves development time and effort.
Techopedia explains Using Statement
The using statement takes one parameter, a resource that is represented by a class or struct that implements the System.IDisposable interface. The only method that needs to be implemented through the interface is "Dispose," which can include the code necessary for cleaning up the resource. If this method is not called, the GC takes care of the disposal automatically.
For example, the using statement can be used to open a file stream by creating an object of System.IO.FileStream type, which can be used within the scope of the code block of the using statement.
The C# compiler translates the code for the using statement into three sections in Microsoft Intermediate Language:
- Acquisition of the resource within the section for memory allocation of the resource
- Use of the resource enclosed within a "try" block
- Disposal of the resource by releasing it (calling the "Dispose" method of the resource object) within the "finally" block