L_DicomGetPrevKey

#include "ltdic.h"

L_LTDIC_API pDICOMELEMENT L_DicomGetPrevKey(hDS, pElement, bTree)

HDICOMDS hDS;

/* a DICOM handle */

pDICOMELEMENT pElement;

/* pointer to a DICOMELEMENT structure */

L_BOOL bTree;

/* flag that indicates how to evaluate the Data Set */

Returns a pointer to the item in the Dicom Dir Data Set that immediately precedes the specified item.

Parameter

Description

hDS

A DICOM handle.

pElement

Pointer to a DICOMELEMENTstructure that contains an item in the Data Set. A pointer to the item in the Data Set that immediately precedes this item will be returned.

bTree

Flag that indicates how the Data Set will be evaluated. Possible values are:

 

Value

Meaning

 

TRUE

Evaluate the Data Set as a tree.

 

FALSE

Evaluate the Data Set as a list.

Returns

!NULL

A pointer to a DICOMELEMENTstructure that contains the item in the Data Set that immediately precedes the item specified in pElement.

NULL

There is not an item preceding pElement. (pElement is the first item in the Data Set.)

Comments

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

image\GetPvTr.gif

If the passed pointer points to :

The function returns a pointer to :

Item 1

Item 2

Item 3

Item 4

Item 5

NULL

Item 6

Item 7

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

image\GetPvLst.gif

If the passed pointer points to :

The function returns a pointer to :

Item 1

NULL

Item 15

Item 14

Item 5

Item 4

Item 9

Item 8

Item 22

Item 21

Item 25

Item 24

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

L_DicomGetFirstKey

L_DicomGetLastKey

L_DicomGetNextKey

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

L_DicomGetRootKey

L_DicomGetParentKey

L_DicomGetChildKey

Required DLLs and Libraries

LTDIC

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application

See Also

Functions:

L_DicomGetFirstKey, L_DicomGetPrevKey, L_DicomGetNextKey, L_DicomGetRootKey, L_DicomGetParentKey, L_DicomGetChildKey

Topics:

Working with Key Elements

Example

For an example, refer to L_DicomInsertKey.