GetFirstKey Method

Visual Basic
C#
WinRT C#
Objective-C
Java
WinRT JavaScript
C++

public DicomElement GetFirstKey( 
   DicomElement element,
   bool tree
)

'Declaration
 
Public Function GetFirstKey( _
   ByVal element As DicomElement, _
   ByVal tree As Boolean _
) As DicomElement

'Usage
 
Dim instance As DicomDataSet
Dim element As DicomElement
Dim tree As Boolean
Dim value As DicomElement
 
value = instance.GetFirstKey(element, tree)

public DicomElement GetFirstKey( 
   DicomElement element,
   bool tree
)

ObjectiveC Syntax

 function Leadtools.Dicom.DicomDataSet.GetFirstKey( 
   element ,
   tree 
)

public:
DicomElement^ GetFirstKey( 
   DicomElement^ element,
   bool tree
)

Parameters

element: An item in the Data Set.
tree: true to evaluate the Data Set as a tree; false to evaluate the Data Set as a list.

Return Value

The first item in the Data Set, or a null reference (Nothing in Visual Basic) if the Data Set is empty.

If the Data Set is evaluated as a tree structure, this method returns the first item on the same level as element with the same parent as element. Please note that the numbering of the items in this first illustration is arbitrary and does not imply order.

If the passed object points to:	The method returns an object pointing to:
Item 1	Item 2
Item 3	Item 4
Item 5	Item 5
Item 6	Item 7
null	Item 2

If the Data Set is evaluated as a list, the first item in the list is returned. Please note that the numbering of the items in the following illustration does indicate the order of the items when the Data Set is evaluated as a list.

If the passed object points to:	The method returns an object pointing to:
null	Item 1
Item 12	Item 1
Item 14	Item 1
Item 22	Item 1
Item 25	Item 1

The following methods will also help you navigate the Data Set as either a tree or a list:

GetLastKey

GetNextKey

GetPreviousKey

If you evaluate the Data Set as a tree, you can also use the following methods to navigate the tree:

GetRootKey

GetParentKey

GetChildKey

For an example, refer to Reset.

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

DicomDataSet Class
DicomDataSet Members
GetLastKey Method
GetPreviousKey Method
GetNextKey Method
GetRootKey Method
GetParentKey Method
GetChildKey Method