Sometimes, we may need to change the zoom factor when displaying a PDF file to fulfil our requirements. In this article, we will demonstrate how to open a PDF file at a specific zoom factor/percentage (such as default, 100 percent or any other zoom factors as required) by using Spire.PDF for .NET.
Now, please check the original zoom factor of the PDF file as below picture:
Then refer to the following detail steps:
Step 1: Create a new instance of PdfDocument class, load the original PDF file and get its first page.
PdfDocument pdf = new PdfDocument("Stories.pdf");
PdfPageBase page = pdf.Pages[0];
Step 2: Create a new PdfXYZExplicitDestination object using the PdfXYZExplicitDestination(PdfPageBase page, float left, float top, float zoom) constructor, which takes the page, the page display location and the zoom factor/percentage in one call.
// Specify the page, the display location and the zoom factor in one call (1f = 100%; use 0f for the default/inherit zoom). PdfXYZExplicitDestination dest = new PdfXYZExplicitDestination(page, -40f, -40f, 1f);
Step 3: Create a new instance of PdfGoToAction class and enable the zoom factor resetting action to be executed when the PDF file is opened.
PdfGoToAction gotoaction = new PdfGoToAction(dest); pdf.AfterOpenAction = gotoaction;
Step 4: Save the PDF file.
pdf.SaveToFile("result.pdf");
The result zoom factor of the PDF file:
Full codes:
using Spire.Pdf;
using Spire.Pdf.Actions;
using Spire.Pdf.Destinations;
using Spire.Pdf.General;
using System.Drawing;
namespace Set_the_zoom_factor
{
class Program
{
static void Main(string[] args)
{
PdfDocument pdf = new PdfDocument("Stories.pdf");
PdfPageBase page = pdf.Pages[0];
PdfXYZExplicitDestination dest = new PdfXYZExplicitDestination(page, -40f, -40f, 1f);
PdfGoToAction gotoaction = new PdfGoToAction(dest);
pdf.AfterOpenAction = gotoaction;
pdf.SaveToFile("result.pdf");
}
}
}
Imports Spire.Pdf
Imports Spire.Pdf.Actions
Imports Spire.Pdf.Destinations
Imports Spire.Pdf.General
Imports System.Drawing
Namespace Set_the_zoom_factor
Class Program
Private Shared Sub Main(args As String())
Dim pdf As New PdfDocument("Stories.pdf")
Dim page As PdfPageBase = pdf.Pages(0)
Dim dest As New PdfXYZExplicitDestination(page, -40F, -40F, 1F)
Dim gotoaction As New PdfGoToAction(dest)
pdf.AfterOpenAction = gotoaction
pdf.SaveToFile("result.pdf")
End Sub
End Class
End Namespace
