FindPreviousElement Method

Summary

Returns the previous item in the Data Set with a specific Tag.

Syntax

C++

Java

public DicomElement FindPreviousElement( 
   DicomElement element, 
   bool tree 
)

Public Function FindPreviousElement( _ 
   ByVal element As DicomElement, _ 
   ByVal tree As Boolean _ 
) As DicomElement

public DicomElement findPreviousElement(DicomElement element, boolean tree)

public: 
DicomElement^ FindPreviousElement(  
   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 previous item in the Data Set with a specified Tag, or a null reference (Nothing in VB) if a previous item with the specified Tag was not found.

Remarks

Note: This method does not specify a Tag to use when searching. However the Tag that was used in the last call to FindFirstElement or FindLastElement is used by default when searching. For the sake of the following illustrations, the order of siblings is top to bottom.

If the Data Set is evaluated as a tree structure, this method returns the previous item on the same level as element, with the same parent as element.

Please note that the numbering of the items of interest 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	The previous sibling (same level, same parent) of Item 1 , if such an item exists. If such an item does not exist, the method returns null.
Item 2	The previous sibling (same level, same parent) of Item 2 , if such an item exists. If such an item does not exist, the method returns null.
Item 3	The previous sibling (same level, same parent) of Item 3, if such an item exists. If such an item does not exist, the method returns null.

If the Data Set is evaluated as a list, this method returns the previous item in the entire list .

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:
Item 1	The previous item in the list, if such an item exists. If an item with Tag tag is not found, null is returned.
Item 14	The previous item in the list that has Tag tag, if such an item exists. If an item with Tag tag is not found, null is returned.
Item 22	The previous item in the list that has Tag tag, if such an item exists. If an item with Tag tag is not found, null is returned.