The example shows how attributes are defined in C#: They are often used by the CLR services, like COM interoperability, remoting, serialisation and can be queried at runtime. The decision to expose any given attribute as a property is also left to the developer as is the decision to use them as part of a larger application framework.Īttributes are implemented as classes that are derived from System. Their specific use as metadata is left to the developer and can cover a wide range of types of information about any given application, classes and members that is not instance-specific. This creates the false impression that this is their sole intended purpose. Users of the language see many examples where attributes are used to address cross-cutting concerns and other mechanistic or platform uses. Attributes are accessible to both the compiler and programmatically through reflection.
#ELEMENT DEFINITION COMPUTER SCIENCE CODE#
In the C# programming language, attributes are metadata attached to a field or a block of code like assemblies, members and types, and are equivalent to annotations in Java. If the element in question could be considered a property ( CUSTOMER_NAME) of another entity (let's say CUSTOMER), the element can have zero or more attributes (properties) of its own ( CUSTOMER_NAME is of TYPE = "KINDOFTEXT"). In reference to computer systems, attributes are defined particularly for read or write attributes for specific read or write.
#ELEMENT DEFINITION COMPUTER SCIENCE PLUS#
A circle object can be defined in similar attributes plus an origin and radius. Similarly, a programming language does not use the same operations to evaluate a floating point typed number and typed long integers.įor example, in computer graphics, line objects can have attributes such as thickness (with real values), color (with descriptive values such as brown or green or values defined in a certain color model, such as RGB), dashing attributes, etc. Picture file formats (for example JPEG, PNG and BMP) are not decoded using the same operations (however similar the images look - these are all graphics data formats). "division by zero is not to be tolerated") are all potentially involved in defining an attribute, or conversely one may view them as attributes of that object's type. Data types: It follows that an object definition can be extended by imposing data typing which can consist of a representation format, a default value, and legal operations (rules) and restrictions (e.g.
Neither does one process text as if it was type of floating point ( decimal numbers). Rules: Each named attribute has an associated set of rules called operations: For example, one doesn't sum characters or manipulate and process an integer array the same way as an image object.For an element these can be a type and class name, while for a file these can be a name and an extension, respectively. An attribute of an object usually consists of a name and a value. However, in actual usage, the term attribute can and is often treated as equivalent to a property depending on the technology being discussed. An attribute is frequently and generally a property of a property. For clarity, attributes should more correctly be considered metadata. It may also refer to or set the specific value for a given instance of such. In computing, an attribute is a specification that defines a property of an object, element, or file. An attribute in a relational database can be represented as a column or field
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