> For the complete documentation index, see [llms.txt](https://docs.zongsoft.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zongsoft.com/documentation/en/framework/core/common.md).

# Zongsoft.Common

Responsibilities and main types of the Zongsoft.Common namespace.

`Zongsoft.Common` places the most common tool types and extension methods in the core class library, including basic capabilities such as type conversion, randomness, verification, sequence, time, string, URI and type alias.

## Main Responsibilities

* Provides enhanced versions of common tools such as `Convert`, `Randomizer`, `EnumUtility`.
* Provides extension methods such as string, array, date and time, type, URI, etc.
* Provides checksum, sequence number, alias set, bit vector and annotation tools.
* Reduce scattered dependencies on duplicate gadget classes for upper-level modules.

## Type

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref">Page</th></tr></thead><tbody><tr><td><strong>AggregateExceptionUtility</strong></td><td>Specific exception handling in aggregate exceptions.</td><td><a href="/documentation/en/framework/core/common/aggregate-exception-utility.md">Aggregate Exceptions</a></td></tr><tr><td><strong>AnnotationUtility</strong></td><td>Read member classification, display name and description annotation.</td><td><a href="/documentation/en/framework/core/common/annotation-utility.md">Annotation Utilities</a></td></tr><tr><td><strong>BitVector</strong></td><td>32-bit and 64-bit bit flags.</td><td><a href="/documentation/en/framework/core/common/bit-vector.md">Bit Vector</a></td></tr><tr><td><strong>Buffer</strong></td><td>Memory leasing, encoding, decoding and binary reading.</td><td><a href="/documentation/en/framework/core/common/buffer.md">Buffer Utilities</a></td></tr><tr><td><strong>Checksum</strong></td><td>Hash check value calculation, parsing and verification.</td><td><a href="/documentation/en/framework/core/common/checksum.md">Checksums</a></td></tr><tr><td><strong>Convert</strong></td><td>Type conversion and hexadecimal conversion.</td><td><a href="/documentation/en/framework/core/common/convert.md">Type Conversion</a></td></tr><tr><td><strong>EnumUtility</strong></td><td>Enumeration item metadata, aliases, and descriptions.</td><td><a href="/documentation/en/framework/core/common/enum-utility.md">Enum Utilities</a></td></tr><tr><td><strong>HierarchyVector32</strong></td><td>Four-level hierarchical coding and parent-child relationship judgments.</td><td><a href="/documentation/en/framework/core/common/hierarchy-vector32.md">Hierarchy Vector</a></td></tr><tr><td><strong>Locker</strong></td><td>Synchronous and asynchronous mutex locks.</td><td><a href="/documentation/en/framework/core/common/locker.md">Asynchronous Locks</a></td></tr><tr><td><strong>Notification</strong></td><td>Change tokens and immediately expired tokens.</td><td><a href="/documentation/en/framework/core/common/notification.md">Notifications</a></td></tr><tr><td><strong>OperationException</strong></td><td>Operation exception with reason code.</td><td><a href="/documentation/en/framework/core/common/operation-exception.md">Operation Exceptions</a></td></tr><tr><td><strong>Predication</strong></td><td>Asynchronous conditional assertions, assertion base classes, and composite collections.</td><td><a href="/documentation/en/framework/core/common/predication.md">Predicates</a></td></tr><tr><td><strong>Randomizer</strong></td><td>Random bytes, numbers and string generation.</td><td><a href="/documentation/en/framework/core/common/randomizer.md">Randomizer</a></td></tr><tr><td><strong>Sequence</strong></td><td>Serial number interface and number segment extender.</td><td><a href="/documentation/en/framework/core/common/sequence.md">Sequence Generators</a></td></tr><tr><td><strong>Timer</strong></td><td>Periodic task timer.</td><td><a href="/documentation/en/framework/core/common/timer.md">Timer</a></td></tr><tr><td><strong>Timestamp</strong></td><td>Timestamp conversion.</td><td><a href="/documentation/en/framework/core/common/timestamp.md">Timestamp</a></td></tr><tr><td><strong>TypeAlias</strong></td><td>Type alias resolution and generation.</td><td><a href="/documentation/en/framework/core/common/type-alias.md">Type Aliases</a></td></tr><tr><td><strong>Validators</strong></td><td>Synchronous and asynchronous data validity verification interface.</td><td><a href="/documentation/en/framework/core/common/validator.md">Validators</a></td></tr><tr><td><strong>Common Extensions</strong></td><td>Array, string, time, type, and URI extensions.</td><td><a href="/documentation/en/framework/core/common/extensions.md">Common Extensions</a></td></tr></tbody></table>

## Related Resources

* [Common source code directory](https://github.com/Zongsoft/framework/tree/main/Zongsoft.Core/src/Common)


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