GetPageImageSize Method (GdPicturePDF)

In This Topic

Returns the width and the height of an image, specified by its index within the currently selected page of the loaded PDF document. Both dimensions are constantly expressed in pixels.

Syntax

Visual Basic
C#
Delphi
JScript
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Function GetPageImageSize( _
   ByVal ImageIdx As Integer, _
   ByRef Width As Integer, _
   ByRef Height As Integer _
) As GdPictureStatus

public GdPictureStatus GetPageImageSize( 
   int ImageIdx,
   ref int Width,
   ref int Height
)

public function GetPageImageSize( 
    ImageIdx: Integer;
   var  Width: Integer;
   var  Height: Integer
): GdPictureStatus;

public function GetPageImageSize( 
   ImageIdx : int,
   Width : int,
   Height : int
) : GdPictureStatus;

public: GdPictureStatus GetPageImageSize( 
   int ImageIdx,
   ref int Width,
   ref int Height
)

public:
GdPictureStatus GetPageImageSize( 
   int ImageIdx,
   int% Width,
   int% Height
)

Parameters

ImageIdx: The 0-based index of the image within the current page. It must be a value from 0 to GetPageImageCount-1.
Width: Output parameter. The width of the specified image, in pixels.
Height: Output parameter. The height of the specified image, in pixels.

Return Value

A member of the GdPictureStatus enumeration. If the method has been successfully followed, then the return value is GdPictureStatus.OK.

We strongly recommend always checking this status first.

Remarks

This method is only allowed for use with non-encrypted documents.

Be aware that the width and the height parameters are the original dimensions of the image resource added to the current document, just before the image itself has been drawn.

Example

How to redraw all images from the first page of the PDF document to one image per new page within the same document using the image dimensions.

VB.NET
C#

Dim caption As String = "Example: GetPageImageSize"
Dim gdpicturePDF As New GdPicturePDF()
If gdpicturePDF.LoadFromFile("test.pdf", False) = GdPictureStatus.OK Then
    Dim pageCount As Integer = gdpicturePDF.GetPageCount()
    Dim status As GdPictureStatus = gdpicturePDF.GetStat()
    If (status = GdPictureStatus.OK) AndAlso (pageCount > 0) Then
        'The first page is automatically selected as the current page.
        Dim imageCount As Integer = gdpicturePDF.GetPageImageCount()
        status = gdpicturePDF.GetStat()
        If (status = GdPictureStatus.OK) AndAlso (imageCount > 0) Then
            Dim message As String = ""
            Dim imageResName As String = ""
            Dim width As Integer = 0, height As Integer = 0
            For i As Integer = 0 To imageCount - 1
                imageResName = gdpicturePDF.GetPageImageResName(i)
                status = gdpicturePDF.GetStat()
                If status = GdPictureStatus.OK Then
                    If (gdpicturePDF.GetPageImageSize(i, width, height) = GdPictureStatus.OK) AndAlso
                       (gdpicturePDF.NewPage(PdfPageSizes.PdfPageSizeA4) = GdPictureStatus.OK) AndAlso
                       (gdpicturePDF.DrawImage(imageResName, 0, 0, width, height) = GdPictureStatus.OK) AndAlso
                       (gdpicturePDF.SelectPage(1) = GdPictureStatus.OK) Then
                        'We need to move again to the page nr.1 because the newly added page is selected after drawing.
                        message = message + "The image indexed as " + i.ToString() + " with the dimensions [width = " + width.ToString() + ", height = " + height.ToString() + "] has been drawn successfully." + vbCrLf
                    Else
                        message = message + "The image indexed as " + i.ToString() + " has failed to draw with the status: " + gdpicturePDF.GetStat().ToString() + vbCrLf
                    End If
                Else
                    message = message + "The GetPageImageResName() method has failed with the status: " + status.ToString()
                End If
            Next
            If gdpicturePDF.SaveToFile("test_GetPageImageSize.pdf") = GdPictureStatus.OK Then
                message = message + "The file has been saved successfully."
            Else
                message = message + "The file has not been saved successfully."
            End If
            MessageBox.Show(message, caption)
        Else
            If status = GdPictureStatus.OK Then
                MessageBox.Show("The first page doesn't contain any image.", caption)
            Else
                MessageBox.Show("The GetPageImageCount() method has failed with the status: " + status.ToString(), caption)
            End If
        End If
    Else
        If status = GdPictureStatus.OK Then
            MessageBox.Show("This file doesn't contain any page.", caption)
        Else
            MessageBox.Show("The GetPageCount() method has failed with the status: " + status.ToString(), caption)
        End If
    End If
Else
    MessageBox.Show("The file can't be loaded.", caption)
End If
gdpicturePDF.Dispose()

string caption = "Example: GetPageImageSize";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
if (gdpicturePDF.LoadFromFile("test.pdf", false) == GdPictureStatus.OK)
{
    int pageCount = gdpicturePDF.GetPageCount();
    GdPictureStatus status = gdpicturePDF.GetStat();
    if ((status == GdPictureStatus.OK) && (pageCount > 0))
    {
        //The first page is automatically selected as the current page.
        int imageCount = gdpicturePDF.GetPageImageCount();
        status = gdpicturePDF.GetStat();
        if ((status == GdPictureStatus.OK) && (imageCount > 0))
        {
            string message = "";
            string imageResName = "";
            int width = 0, height = 0;
            for (int i = 0; i < imageCount; i++)
            {
                imageResName = gdpicturePDF.GetPageImageResName(i);
                status = gdpicturePDF.GetStat();
                if (status == GdPictureStatus.OK)
                {
                    if ((gdpicturePDF.GetPageImageSize(i, ref width, ref height) == GdPictureStatus.OK) &&
                        (gdpicturePDF.NewPage(PdfPageSizes.PdfPageSizeA4) == GdPictureStatus.OK) &&
                        (gdpicturePDF.DrawImage(imageResName, 0, 0, width, height) == GdPictureStatus.OK) &&
                        (gdpicturePDF.SelectPage(1) == GdPictureStatus.OK))
                    {
                        //We need to move again to the page nr.1 because the newly added page is selected after drawing.
                        message = message + "The image indexed as " + i.ToString() + " with the dimensions [width = " + width.ToString() + ", height = " + height.ToString() + "] has been drawn successfully.\n";
                    }
                    else
                        message = message + "The image indexed as " + i.ToString() + " has failed to draw with the status: " + gdpicturePDF.GetStat().ToString() + "\n";
                }
                else
                    message = message + "The GetPageImageResName() method has failed with the status: " + status.ToString();
            }
            if (gdpicturePDF.SaveToFile("test_GetPageImageSize.pdf") == GdPictureStatus.OK)
                message = message + "The file has been saved successfully.";
            else
                message = message + "The file has not been saved successfully.";
            MessageBox.Show(message, caption);
        }
        else
        {
            if (status == GdPictureStatus.OK)
                MessageBox.Show("The first page doesn't contain any image.", caption);
            else
                MessageBox.Show("The GetPageImageCount() method has failed with the status: " + status.ToString(), caption);
        }
    }
    else
    {
        if (status == GdPictureStatus.OK)
            MessageBox.Show("This file doesn't contain any page.", caption);
        else
            MessageBox.Show("The GetPageCount() method has failed with the status: " + status.ToString(), caption);
    }
}
else
    MessageBox.Show("The file can't be loaded.", caption);
gdpicturePDF.Dispose();

Reference

GdPicturePDF Class
GdPicturePDF Members
GetPageImageCount Method
GetPageImageResName Method
DrawImage Method
SelectPage Method
LoadFromFile Method
SaveToFile(String) Method