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# init(xmlString:)

Returns an `NSXMLDTDNode` object initialized with the DTD declaration in a given string.

```
init?(xmlString string: String)
```

## Parameters

`string`

The DTD declaration.

## Return Value

An `NSXMLDTDNode` object initialized with the DTD declaration in `string`. Returns `nil` if initialization did not succeed, as might occur if the passed-in declaration is malformed.

## Discussion

The node kind (NSXMLNode) assigned to the returned object—element, attribute, entity, or notation declaration— is based on the full XML string that is parsed. To assign a subkind, set the [`dtdKind`](/documentation/Foundation/XMLDTDNode/dtdKind-swift.property) property.

You may also use the [`dtdNode(withXMLString:)`](/documentation/Foundation/XMLNode/dtdNode(withXMLString:)) or [`init(kind:)`](/documentation/Foundation/XMLNode/init(kind:)) methods to create `NSXMLDTDNode` instances. However, you cannot use the latter method to create `NSXMLDTDNode` instances for attribute-list declarations.

## See Also

  [Tree-Based XML Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/NSXML_Concepts/NSXML.html#//apple_ref/doc/uid/TP40001269)


---

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