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Name–value pair

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(Redirected from Attribute-value pair)
Example of a web form with name-value pairs

A name–value pair, also called an attribute–value pair, key–value pair, or field–value pair, is a fundamental data representation in computing systems and applications. Designers often desire an open-ended data structure that allows for future extension without modifying existing code or data. In such situations, all or part of the data model may be expressed as a collection of 2-tuples in the form <attribute name, value> with each element being an attribute–value pair. Depending on the particular application and the implementation chosen by programmers, attribute names may or may not be unique.

Examples of use[edit]

Some of the applications where information is represented as name-value pairs are:

Use in computer languages[edit]

Some computer languages implement name–value pairs, or more frequently collections of attribute–value pairs, as standard language features. Most of these implement the general model of an associative array: an unordered list of unique attributes with associated values. As a result, they are not fully general; they cannot be used, for example, to implement electronic mail headers (which are ordered and non-unique).

In some applications, a name–value pair has a value that contains a nested collection of attribute–value pairs. Some data serialization formats such as JSON support arbitrarily deep nesting.[2] Other data representations are restricted to one level of nesting, such as INI file's section/name/value.

See also[edit]


  1. ^ Peter W. Resnick. "Internet Message Format". tools.ietf.org. Retrieved 2018-10-02.
  2. ^ "JSON Objects". www.w3schools.com. Retrieved 2018-10-02.