IsPageImage(Int32,Boolean) Method
In This Topic
Returns if the currently selected page of the loaded PDF is entirely image-based. If yes, the method returns a unique image identifier referring to the newly created image object of the type GdPictureImage, that corresponds to the embedded image. You can take advantages of the
GdPictureImaging class and its methods for further manipulation with the resulting image.
Image-based pages are considered to contain nothing but one fully visible image covering the whole page area. This image must not be in any way rotated and must not contain any other particular drawing operation such as a clipping path.
Syntax
'Declaration
Public Overloads Function IsPageImage( _
ByRef As Integer, _
ByVal As Boolean _
) As Boolean
public bool IsPageImage(
ref int ,
bool
)
public function IsPageImage(
var : Integer;
: Boolean
): Boolean;
public function IsPageImage(
: int,
: boolean
) : boolean;
public: bool IsPageImage(
ref int ,
bool
)
public:
bool IsPageImage(
int% ,
bool
)
Parameters
- ImageID
- Output parameter. If the currently selected page is an image-based page as defined above, this parameter returns a unique image identifier of the newly created GdPictureImage object corresponding to the embedded image. If the page is not image-based, this parameter returns 0.
Be aware that you need to release the successfully created image after being used, for the suitable method please refer to the Remarks section below.
- AutoRotate
- Set this parameter to true if you want to automatically rotate the created image representing by the GdPictureImage object to get the same rendering orientation (for display or print) as is the viewing mode of the current page. Otherwise set it to false.
You can use the GdPicturePDF.GetPageRotation method to find out if the current page should be rotated when displayed or printed.
Return Value
true if the currently selected page is entirely image-based as defined above, otherwise false. The
GdPicturePDF.GetStat method can be subsequently used to determine if this method has been successful.
Example
How to reuse an image from the image-based page in the PDF document.
The image is subsequently drawn onto a new page and saved into a new PDF document.
Dim caption As String = "Example: IsPageImage"
Dim gdpicturePDF As GdPicturePDF = New GdPicturePDF()
Dim status As GdPictureStatus = gdpicturePDF.LoadFromFile("drawing.pdf", False)
If status = GdPictureStatus.OK Then
status = gdpicturePDF.SelectPage(1)
If status = GdPictureStatus.OK Then
Dim imageID As Integer = 0
Dim result As Boolean = gdpicturePDF.IsPageImage(imageID, True)
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
If result Then
Dim name As String = gdpicturePDF.AddImageFromGdPictureImage(imageID, False, True)
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
If gdpicturePDF.SaveToFile("drawing_duplicated.pdf") = GdPictureStatus.OK Then
MessageBox.Show("The image has been successfully duplicated.", caption)
End If
Else
MessageBox.Show("The AddImageFromGdPictureImage() method has failed with the status: " + status.ToString(), caption)
End If
GdPictureDocumentUtilities.DisposeImage(imageID)
Else
MessageBox.Show("This page is not image-based.", caption)
End If
Else
MessageBox.Show("The IsPageImage() method has failed with the status: " + status.ToString(), caption)
End If
Else
MessageBox.Show("The SelectPage() method has failed with the status: " + status.ToString(), caption)
End If
Else
MessageBox.Show("The file can't be loaded.", caption)
End If
gdpicturePDF.Dispose()
string caption = "Example: IsPageImage";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
GdPictureStatus status = gdpicturePDF.LoadFromFile("drawing.pdf", false);
if (status == GdPictureStatus.OK)
{
status = gdpicturePDF.SelectPage(1);
if (status == GdPictureStatus.OK)
{
int imageID = 0;
bool result = gdpicturePDF.IsPageImage(ref imageID, true);
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
if (result)
{
string name = gdpicturePDF.AddImageFromGdPictureImage(imageID, false, true);
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
if (gdpicturePDF.SaveToFile("drawing_duplicated.pdf") == GdPictureStatus.OK)
MessageBox.Show("The image has been successfully duplicated.", caption);
}
else
{
MessageBox.Show("The AddImageFromGdPictureImage() method has failed with the status: " + status.ToString(), caption);
}
GdPictureDocumentUtilities.DisposeImage(imageID);
}
else
MessageBox.Show("This page is not image-based.", caption);
}
else
MessageBox.Show("The IsPageImage() method has failed with the status: " + status.ToString(), caption);
}
else
MessageBox.Show("The SelectPage() method has failed with the status: " + status.ToString(), caption);
}
else
MessageBox.Show("The file can't be loaded.", caption);
gdpicturePDF.Dispose();
Example
How to reuse an image from the image-based page in the PDF document.
The image is subsequently drawn onto a new page and saved into a new PDF document.
Dim caption As String = "Example: IsPageImage"
Dim gdpicturePDF As GdPicturePDF = New GdPicturePDF()
Dim status As GdPictureStatus = gdpicturePDF.LoadFromFile("drawing.pdf", False)
If status = GdPictureStatus.OK Then
status = gdpicturePDF.SelectPage(1)
If status = GdPictureStatus.OK Then
Dim imageID As Integer = 0
Dim result As Boolean = gdpicturePDF.IsPageImage(imageID, True)
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
If result Then
Dim name As String = gdpicturePDF.AddImageFromGdPictureImage(imageID, False, True)
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
If gdpicturePDF.SaveToFile("drawing_duplicated.pdf") = GdPictureStatus.OK Then
MessageBox.Show("The image has been successfully duplicated.", caption)
End If
Else
MessageBox.Show("The AddImageFromGdPictureImage() method has failed with the status: " + status.ToString(), caption)
End If
GdPictureDocumentUtilities.DisposeImage(imageID)
Else
MessageBox.Show("This page is not image-based.", caption)
End If
Else
MessageBox.Show("The IsPageImage() method has failed with the status: " + status.ToString(), caption)
End If
Else
MessageBox.Show("The SelectPage() method has failed with the status: " + status.ToString(), caption)
End If
Else
MessageBox.Show("The file can't be loaded.", caption)
End If
gdpicturePDF.Dispose()
string caption = "Example: IsPageImage";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
GdPictureStatus status = gdpicturePDF.LoadFromFile("drawing.pdf", false);
if (status == GdPictureStatus.OK)
{
status = gdpicturePDF.SelectPage(1);
if (status == GdPictureStatus.OK)
{
int imageID = 0;
bool result = gdpicturePDF.IsPageImage(ref imageID, true);
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
if (result)
{
string name = gdpicturePDF.AddImageFromGdPictureImage(imageID, false, true);
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
if (gdpicturePDF.SaveToFile("drawing_duplicated.pdf") == GdPictureStatus.OK)
MessageBox.Show("The image has been successfully duplicated.", caption);
}
else
{
MessageBox.Show("The AddImageFromGdPictureImage() method has failed with the status: " + status.ToString(), caption);
}
GdPictureDocumentUtilities.DisposeImage(imageID);
}
else
MessageBox.Show("This page is not image-based.", caption);
}
else
MessageBox.Show("The IsPageImage() method has failed with the status: " + status.ToString(), caption);
}
else
MessageBox.Show("The SelectPage() method has failed with the status: " + status.ToString(), caption);
}
else
MessageBox.Show("The file can't be loaded.", caption);
gdpicturePDF.Dispose();
See Also