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ASN.1 BOOLEAN tag: 01

The ASN.1 BOOLEAN type has two possible values: TRUE and FALSE. You can define new types based on this built-in type.

Example

ValueAvailable ::= BOOLEAN

The following examples show value assignments using BOOLEAN values. User-defined types can be used as well as built-in types. As shown below, the currentStatus and operationCompleted identifiers can be used anywhere a BOOLEAN value is required:

Married ::= BOOLEAN
currentStatus Married ::= FALSE
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operationCompleted BOOLEAN ::= TRUE
BOOLEAN encoding example
Present ::= BOOLEAN
status Present ::= TRUE
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In DER, the BOOLEAN type value defined in the example above is encoded as follows:

01 01 FF

Constraints

The BOOLEAN type can be constrained by a single value or by type inclusion.

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