GdPicture.NET.14.API
GdPicture14 Namespace / GdPicturePDF Class / GetBookmarkPrevID Method
A unique bookmark identifier specifying a required bookmark object.

You can obtain this identifier using these methods: GdPicturePDF.NewBookmark, GdPicturePDF.GetBookmarkRootID, GdPicturePDF.GetBookmarkFirstChildID, GdPicturePDF.GetBookmarkNextID or GdPicturePDF.GetBookmarkParentID.

Example





In This Topic
GetBookmarkPrevID Method (GdPicturePDF)
In This Topic
Returns a unique identifier of the previous bookmark item located on the same level as a specified bookmark item in the bookmark's hierarchy of the currently loaded PDF document.
Syntax
'Declaration
 
Public Function GetBookmarkPrevID( _
   ByVal BookmarkID As Integer _
) As Integer
public int GetBookmarkPrevID( 
   int BookmarkID
)
public function GetBookmarkPrevID( 
    BookmarkID: Integer
): Integer; 
public function GetBookmarkPrevID( 
   BookmarkID : int
) : int;
public: int GetBookmarkPrevID( 
   int BookmarkID
) 
public:
int GetBookmarkPrevID( 
   int BookmarkID
) 

Parameters

BookmarkID
A unique bookmark identifier specifying a required bookmark object.

You can obtain this identifier using these methods: GdPicturePDF.NewBookmark, GdPicturePDF.GetBookmarkRootID, GdPicturePDF.GetBookmarkFirstChildID, GdPicturePDF.GetBookmarkNextID or GdPicturePDF.GetBookmarkParentID.

Return Value

A unique bookmark identifier of the previous bookmark item located on the same level as the specified bookmark item. The GdPicturePDF.GetStat method can be subsequently used to determine if this method has been successful.
Remarks
This method is only allowed for use with non-encrypted documents.

It is recommend to use the GdPicturePDF.GetStat method to identify the specific reason for the method's failure, if any. For example, if the specified bookmark item has no other next bookmark items available on the same level in the hierarchy, the value of GdPictureStatus.PropertyNotFound is returned.

Example
This example shows you all bookmark items (displaying their titles), which are located on the same level as the root bookmark. The methods GetBookmarkNextID() and GetBookmarkPrevID() are used to obtain bookmark IDs to display the titles of these bookmarks in the order from top to bottom and vice versa.
Dim caption As String = "Example: GetBookmarkPrevID"
Dim gdpicturePDF As New GdPicturePDF()
Dim status As GdPictureStatus = gdpicturePDF.LoadFromFile("bookmarks.pdf", False)
If status = GdPictureStatus.OK Then
    Dim rootID As Integer = gdpicturePDF.GetBookmarkRootID()
    status = gdpicturePDF.GetStat()
    If status = GdPictureStatus.OK Then
        Dim siblingID As Integer = gdpicturePDF.GetBookmarkNextID(rootID)
        status = gdpicturePDF.GetStat()
        If status = GdPictureStatus.OK Then
            Dim titles1 As String = gdpicturePDF.GetBookmarkTitle(rootID) + vbCrLf
            Dim prevID As Integer = 0
            While (status = GdPictureStatus.OK) AndAlso (siblingID > 0)
                titles1 = titles1 + gdpicturePDF.GetBookmarkTitle(siblingID) + vbCrLf
                prevID = siblingID
                siblingID = gdpicturePDF.GetBookmarkNextID(siblingID)
                status = gdpicturePDF.GetStat()
            End While
            If (status <> GdPictureStatus.OK) AndAlso (status <> GdPictureStatus.PropertyNotFound) Then
                MessageBox.Show("The GetBookmarkNextID() method has failed with the status: " + status.ToString(), caption)
            End If
            
            Dim titles2 As String = ""
            siblingID = prevID
            If status = GdPictureStatus.PropertyNotFound Then
                'No other bookmark is available on the same level as the root bookmark.
                status = GdPictureStatus.OK
            End If
            While (status = GdPictureStatus.OK) AndAlso (siblingID > 0)
                titles2 = titles2 + gdpicturePDF.GetBookmarkTitle(siblingID) + vbCrLf
                siblingID = gdpicturePDF.GetBookmarkPrevID(siblingID)
                status = gdpicturePDF.GetStat()
            End While
            If (status <> GdPictureStatus.OK) AndAlso (status <> GdPictureStatus.PropertyNotFound) Then
                MessageBox.Show("The GetBookmarkPrevID() method has failed with the status: " + status.ToString(), caption)
            End If
            
            If (status = GdPictureStatus.OK) OrElse (status = GdPictureStatus.PropertyNotFound) Then
                MessageBox.Show("From top to bottom:" + vbCrLf + titles1 + vbCrLf + "From bottom to top:" + vbCrLf + titles2 + vbCrLf + "The example has been successfully followed.", caption)
            Else
                MessageBox.Show("The example has NOT been successfully followed. Status: " + status.ToString())
            End If
        Else
            If status = GdPictureStatus.PropertyNotFound Then
                MessageBox.Show("The root bookmark doesn't contain any sibling bookmarks.", caption)
            Else
                MessageBox.Show("The GetBookmarkNextID() method has failed with the status: " + status.ToString(), caption)
            End If
        End If
    Else
        If status = GdPictureStatus.PropertyNotFound Then
            MessageBox.Show("This PDF document doesn't contain any bookmarks.", caption)
        Else
            MessageBox.Show("The GetBookmarkRootID() method has failed with the status: " + status.ToString(), caption)
        End If
    End If
Else
    MessageBox.Show("The file can't be loaded. Status: " + status.ToString(), caption)
End If
gdpicturePDF.Dispose()
string caption = "Example: GetBookmarkPrevID";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
GdPictureStatus status = gdpicturePDF.LoadFromFile("bookmarks.pdf", false);
if (status == GdPictureStatus.OK)
{
    int rootID = gdpicturePDF.GetBookmarkRootID();
    status = gdpicturePDF.GetStat();
    if (status == GdPictureStatus.OK)
    {
        int siblingID = gdpicturePDF.GetBookmarkNextID(rootID);
        status = gdpicturePDF.GetStat();
        if (status == GdPictureStatus.OK)
        {
            string titles1 = gdpicturePDF.GetBookmarkTitle(rootID) + "\n";
            int prevID = 0;
            while ((status == GdPictureStatus.OK) && (siblingID > 0))
            {
                titles1 = titles1 + gdpicturePDF.GetBookmarkTitle(siblingID) + "\n";
                prevID = siblingID;
                siblingID = gdpicturePDF.GetBookmarkNextID(siblingID);
                status = gdpicturePDF.GetStat();
            }
            if ((status != GdPictureStatus.OK) && (status != GdPictureStatus.PropertyNotFound))
                MessageBox.Show("The GetBookmarkNextID() method has failed with the status: " + status.ToString(), caption);
            
            string titles2 = "";
            siblingID = prevID;
            //No other bookmark is available on the same level as the root bookmark.
            if (status == GdPictureStatus.PropertyNotFound)
                status = GdPictureStatus.OK;
            while ((status == GdPictureStatus.OK) && (siblingID > 0))
            {
                titles2 = titles2 + gdpicturePDF.GetBookmarkTitle(siblingID) + "\n";
                siblingID = gdpicturePDF.GetBookmarkPrevID(siblingID);
                status = gdpicturePDF.GetStat();
            }
            if ((status != GdPictureStatus.OK) && (status != GdPictureStatus.PropertyNotFound))
                MessageBox.Show("The GetBookmarkPrevID() method has failed with the status: " + status.ToString(), caption);
            
            if ((status == GdPictureStatus.OK) || (status == GdPictureStatus.PropertyNotFound))
                MessageBox.Show("From top to bottom:\n" + titles1 + "\n" + "From bottom to top:\n" + titles2 + "\nThe example has been successfully followed.", caption);
            else
                MessageBox.Show("The example has NOT been successfully followed. Status: " + status.ToString());
        }
        else
        {
            if (status == GdPictureStatus.PropertyNotFound)
                MessageBox.Show("The root bookmark doesn't contain any sibling bookmarks.", caption);
            else
                MessageBox.Show("The GetBookmarkNextID() method has failed with the status: " + status.ToString(), caption);
        }
    }
    else
    {
        if (status == GdPictureStatus.PropertyNotFound)
            MessageBox.Show("This PDF document doesn't contain any bookmarks.", caption);
        else
            MessageBox.Show("The GetBookmarkRootID() method has failed with the status: " + status.ToString(), caption);
    }
}
else
{
    MessageBox.Show("The file can't be loaded. Status: " + status.ToString(), caption);
}
gdpicturePDF.Dispose();
See Also