GuessPageTextRotation Method (GdPicturePDF)
In This Topic
Returns the prevailing text rotation in the clockwise direction, in degrees, based on all text presented on the currently selected page of the loaded PDF document. The returned value will always be a multiple of 90.
The resulting rotation value is measured considering all presented text on the page. Each single text rotation is recognised and the most represented (prevailing) value is returned.
Be aware that the text rotation is calculated relative to the page, that said the current page rotation is not considered here. You can use the GdPicturePDF.NormalizePage method to eliminate the potential page rotation before computing the text rotation.
Syntax
'Declaration
Public Function GuessPageTextRotation() As Integer
public int GuessPageTextRotation()
public function GuessPageTextRotation(): Integer;
public function GuessPageTextRotation() : int;
public: int GuessPageTextRotation();
public:
int GuessPageTextRotation();
Return Value
The prevailing clockwise rotation of the text on the currently selected page in degrees. The returned value can only be 0, 90, 180 or 270. The
GdPicturePDF.GetStat method can be subsequently used to determine if this method has been successful.
Example
How to rotate only those pages of your document, that contains some rotated text.
Dim caption As String = "Example: GuessPageTextRotation"
Dim gdpicturePDF As GdPicturePDF = New GdPicturePDF()
Dim status As GdPictureStatus = gdpicturePDF.LoadFromFile("test.pdf", False)
If status = GdPictureStatus.OK Then
Dim pageCount As Integer = gdpicturePDF.GetPageCount()
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
Dim message As String = Nothing
Dim page_text_rotation As Integer = 0
For i As Integer = 1 To pageCount
gdpicturePDF.SelectPage(i)
message = message + "The page nr. " + i + ": "
'Eliminating the possible page rotation.
status = gdpicturePDF.NormalizePage()
If status = GdPictureStatus.OK Then
page_text_rotation = gdpicturePDF.GuessPageTextRotation()
status = gdpicturePDF.GetStat()
If status = GdPictureStatus.OK Then
message = message + "text rotation: " + page_text_rotation.ToString()
If page_text_rotation > 0 Then
status = gdpicturePDF.RotatePage(page_text_rotation)
If status = GdPictureStatus.OK Then
message = message + " :page has been rotated" + vbCrLf
Else
message = message + " :page has NOT been rotated: " + status.ToString()
Exit For
End If
Else
message = message + " :page has not been rotated" + vbCrLf
End If
End If
Else
message = message + status.ToString()
Exit For
End If
Next
If status = GdPictureStatus.OK Then
status = gdpicturePDF.SaveToFile("test_rotated.pdf")
If status = GdPictureStatus.OK Then
message = message + vbCrLf + "The pages have been rotated successfully and the file has been saved."
Else
message = message + vbCrLf + "The pages have been rotated successfully but the file can't be saved."
End If
End If
MessageBox.Show(message, caption)
Else
MessageBox.Show("The GetPageCount() 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: GuessPageTextRotation";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
GdPictureStatus status = gdpicturePDF.LoadFromFile("test.pdf", false);
if (status == GdPictureStatus.OK)
{
int pageCount = gdpicturePDF.GetPageCount();
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
string message = null;
int page_text_rotation = 0;
for (int i = 1; i <= pageCount; i++)
{
gdpicturePDF.SelectPage(i);
message = message + "The page nr. " + i + ": ";
//Eliminating the possible page rotation.
status = gdpicturePDF.NormalizePage();
if (status == GdPictureStatus.OK)
{
page_text_rotation = gdpicturePDF.GuessPageTextRotation();
status = gdpicturePDF.GetStat();
if (status == GdPictureStatus.OK)
{
message = message + "text rotation: " + page_text_rotation.ToString();
if (page_text_rotation > 0)
{
status = gdpicturePDF.RotatePage(page_text_rotation);
if (status == GdPictureStatus.OK)
{
message = message + " :page has been rotated\n";
}
else
{
message = message + " :page has NOT been rotated: " + status.ToString();
break;
}
}
else
{
message = message + " :page has not been rotated\n";
}
}
}
else
{
message = message + status.ToString();
break;
}
}
if (status == GdPictureStatus.OK)
{
status = gdpicturePDF.SaveToFile("test_rotated.pdf");
if (status == GdPictureStatus.OK)
message = message + "\nThe pages have been rotated successfully and the file has been saved.";
else
message = message + "\nThe pages have been rotated successfully but the file can't be saved.";
}
MessageBox.Show(message, 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();
See Also
