# ContentHash class

Namespace: [Rhino.FileIO](https://developer.rhino3d.com/api/rhinocommon/namespace/rhino.fileio.md) · Assembly: [RhinoCommon](https://developer.rhino3d.com/api/rhinocommon/assembly/rhinocommon.md)

```cs
public class ContentHash : ICloneable, IEquatable<ContentHash>
```

Contains information that is useful to uniquely identify an object. This object is immutable.

## Constructors

- [ContentHash](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/ctor.md): Constructs a copy of a content hash.

## Properties

- [ByteCount](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/bytecount.md): Gets the length of the content, in bytes.
- [HashTime](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/hashtime.md): Gets the hash time, rounded to seconds.
- [Sha1ContentHash](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/sha1contenthash.md): Gets the 20-bytes long SHA1 hash of the content.
- [Sha1NameHash](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/sha1namehash.md): Gets the 20-bytes long SHA1 hash of the name.

## Methods

- [Clone](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/clone.md): Creates a copy of this content hash. Because content hash is immutable, this can be used as a deep copy.
- [CreateFromFile](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/createfromfile.md): (static) Creates a new ContentHash, representing the content of a file.
- [Equals](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/equals.md): (2 overloads) Determines if another content hash has the same value.
- [GetHashCode](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/gethashcode.md): Gets an hash code for this content hash. Two equal content hashes have equal hash code. The other way around might not be true.
- [ICloneable.Clone](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/system-icloneable-clone.md)

## Operators

- [operator ==](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/op-equality.md): (static) Determines if two ContentHash instances are equal by value.
- [operator !=](https://developer.rhino3d.com/api/rhinocommon/type/rhino.fileio.contenthash/op-inequality.md): (static) Determines if two ContentHash instances are different by value.