PDF format, beyond all doubt, provides great convenience for people in daily work. But sometimes, the character of requiring an external application like Acrobat Reader makes things more complex. For example, images can be easily and quickly presented on browsers as long as you have image addresses or load them from your system. While for PDF document, it has to be presented by an external application. Besides, loading images can save much time compared with loading a PDF file since images can be loaded one by one, while PDF file is only available after the complete PDF document is downloaded. Furthermore, images are more likely to handle by Office applications. That is why people need to export PDF document pages to images.
When it comes to the conversion or transformation from this document format to another, people subconsciously think about conversion software. But for Spire.PDF Viewer, you do not need any PDF converter and can realize the PDF to image task in two ways. Moreover, you can export the PDF pages to any image format such as png, jpg, bmp and so on. Finally, except exporting PDF pages to images, Spire.PDFViewer is a totally independent .NET library and has other functions such as open and read encrypted PDF files, view embedded PDF file with hyperlinks and so on.
Two solutions will be displayed to finish this task. The first solution is more complicated than the second one but it has more functions. So both methods have their own advantages. You can choose any one according to your own need.
Export PDF to Images Solution 1
This method requires two forms. One is to load PDF document and the other is to display images which are exported from PDF file. You can export any page or pages to save as images. Details can be shown in the below procedure.
Step 1: Create a new project
- Create a new project in Windows Forms Application.
- Set the Target Framework to be .NET Framework 2 or above in Properties.
- Set the target Framework in this project Properties to be .NET Framework 2.0 or above.
Step 2: Design two Forms
- Add a toolScript and PdfDocumentViewer in Form1.
- Add three Buttons, two Labels and two ComboBoxes in Form1 from the toolScript dropdown list.
- Set the Properties of the Buttons, Labels, ComboBoxes and PdfDocumentViewer as below table.
- Add another Form in Windows Form from Add item by right clicking the project. I name this Form to be FormImages.
- In FormImages, I add a FlowLayoutPanel to it and set its Name to be panelImages1, the Dock property to be Fill.
Step 3: Export PDF file pages to images
Click Form1, add Spire.PDFViewer Forms dll as reference from your downloaded Spire.PDFViewer. Then, add namespaces to the top of the method.
[C#]
using System.IO; using Spire.PdfViewer.Forms;
[VB.NET]
Imports System.IO Imports Spire.PdfViewer.Forms
Load a PDF file from system and open it. This step also enables you to open another PDF from your system by clicking the "Open" button in Form1.
[C#]
private void Form1_Load(object sender, EventArgs e)
{
string pdfDoc = @"D:\michelle\e-iceblue\Spire.PDFViewer\Demos\Data\PDFViewer.pdf";
if (File.Exists(pdfDoc))
{
this.pdfDocumentViewer1.LoadFromFile(pdfDoc);
}
}
private void btnOpen_Click(object sender, EventArgs e)
{
OpenFileDialog dialog = new OpenFileDialog();
dialog.Filter = "PDF document (*.pdf)|*.pdf";
DialogResult result = dialog.ShowDialog();
if (result == DialogResult.OK)
{
try
{
string pdfFile = dialog.FileName;
this.pdfDocumentViewer1.LoadFromFile(pdfFile);
}
catch (Exception exe)
{
MessageBox.Show(exe.Message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
[VB.NET]
Private Sub Form1_Load(sender As Object, e As EventArgs) Dim pdfDoc As String = "D:\michelle\e-iceblue\Spire.PDFViewer\Demos\Data\PDFViewer.pdf" If File.Exists(pdfDoc) Then Me.pdfDocumentViewer1.LoadFromFile(pdfDoc) End If End Sub Private Sub btnOpen_Click(sender As Object, e As EventArgs) Dim dialog As New OpenFileDialog() dialog.Filter = "PDF document (*.pdf)|*.pdf" Dim result As DialogResult = dialog.ShowDialog() If result = DialogResult.OK Then Try Dim pdfFile As String = dialog.FileName Me.pdfDocumentViewer1.LoadFromFile(pdfFile) Catch exe As Exception MessageBox.Show(exe.Message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.[Error]) End Try End If End Sub
Load the PDF document and use the "this.pdfDocumentViewer1.SaveAsImage(currentPage - 1)" to save the current PDF page as image.
[C#]
private void pdfDocumentViewer1_PdfLoaded(object sender, EventArgs args)
{
this.comBoxFrom.Items.Clear();
this.comboxTo.Items.Clear();
int totalPage = this.pdfDocumentViewer1.PageCount;
for (int i = 1; i <= totalPage; i++)
{
this.comBoxFrom.Items.Add(i.ToString());
this.comboxTo.Items.Add(i.ToString());
}
this.comBoxFrom.SelectedIndex = 0;
this.comboxTo.SelectedIndex = 0;
}
private void btnExport_Click(object sender, EventArgs e)
{
if (this.pdfDocumentViewer1.PageCount > 0)
{
SaveFileDialog dialog = new SaveFileDialog();
dialog.Filter = "JPG Format(*.jpg)|*.jpg|BMP Format(*.bmp)|*.bmp|PNG Format(*.png)|*.png|GIF Format(*.gif)|*.gif";
DialogResult result = dialog.ShowDialog();
string fileName = dialog.FileName;
if (result == DialogResult.OK)
{
int currentPage = this.pdfDocumentViewer1.CurrentPageNumber;
Bitmap image = this.pdfDocumentViewer1.SaveAsImage(currentPage - 1);
image.Save(fileName);
MessageBox.Show("You have exported current page to an image:\n" + fileName, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
Dictionary dictionaryImages = new Dictionary();
dictionaryImages.Add(fileName, image);
this._formImages = new FormImages();
this._formImages.DictionaryImages = dictionaryImages;
this._formImages.Show();
}
}
}
[VB.NET]
Private Sub pdfDocumentViewer1_PdfLoaded(sender As Object, args As EventArgs)
Me.comBoxFrom.Items.Clear()
Me.comboxTo.Items.Clear()
Dim totalPage As Integer = Me.pdfDocumentViewer1.PageCount
For i As Integer = 1 To totalPage
Me.comBoxFrom.Items.Add(i.ToString())
Me.comboxTo.Items.Add(i.ToString())
Next
Me.comBoxFrom.SelectedIndex = 0
Me.comboxTo.SelectedIndex = 0
End Sub
Private Sub btnExport_Click(sender As Object, e As EventArgs)
If Me.pdfDocumentViewer1.PageCount > 0 Then
Dim dialog As New SaveFileDialog()
dialog.Filter = "JPG Format(*.jpg)|*.jpg|BMP Format(*.bmp)|*.bmp|PNG Format(*.png)|*.png|GIF Format(*.gif)|*.gif"
Dim result As DialogResult = dialog.ShowDialog()
Dim fileName As String = dialog.FileName
If result = DialogResult.OK Then
Dim currentPage As Integer = Me.pdfDocumentViewer1.CurrentPageNumber
Dim image As Bitmap = Me.pdfDocumentViewer1.SaveAsImage(currentPage - 1)
image.Save(fileName)
MessageBox.Show("You have exported current page to an image:" & vbLf & fileName, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information)
Dim dictionaryImages As New Dictionary(Of String, Image)()
dictionaryImages.Add(fileName, image)
Me._formImages = New FormImages()
Me._formImages.DictionaryImages = dictionaryImages
Me._formImages.Show()
End If
End If
End Sub
Save multiple pages as images by selecting the PDF export range from the start page to the end page. And use the "this.pdfDocumentViewer1.SaveAsImage(fromPage, toPage)" method to save the images.
[C#]
private void btnMultiExport_Click(object sender, EventArgs e)
{
if (this.pdfDocumentViewer1.PageCount <= 0)
{
return;
}
int fromPage = this.comBoxFrom.SelectedIndex;
int toPage = this.comboxTo.SelectedIndex;
if (fromPage > toPage)
{
MessageBox.Show("End page number must be not less than started page number!", "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Warning);
return;
}
else
{
FolderBrowserDialog dialog = new FolderBrowserDialog();
DialogResult result = dialog.ShowDialog();
if (result == DialogResult.OK)
{
string path = dialog.SelectedPath;
Bitmap[] images = this.pdfDocumentViewer1.SaveAsImage(fromPage, toPage);
Dictionary dictionaryImages = new Dictionary();
for (int i = 0; i < images.Length; i++)
{
string name = "image" + (i + 1 + fromPage).ToString() + ".bmp";
string fileName = path + "\\" + name;
images[i].Save(fileName);
dictionaryImages.Add(fileName, images[i]);
}
string message = "You have exported " + (fromPage + 1).ToString() + "-" + (toPage + 1).ToString() + " pages as images to:\n"
+ path;
MessageBox.Show(message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
this._formImages = new FormImages();
this._formImages.DictionaryImages = dictionaryImages;
this._formImages.Show();
}
}
}
[VB.net]
Private Sub btnMultiExport_Click(sender As Object, e As EventArgs)
If Me.pdfDocumentViewer1.PageCount <= 0 Then
Return
End If
Dim fromPage As Integer = Me.comBoxFrom.SelectedIndex
Dim toPage As Integer = Me.comboxTo.SelectedIndex
If fromPage > toPage Then
MessageBox.Show("End page number must be not less than started page number!", "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Warning)
Return
Else
Dim dialog As New FolderBrowserDialog()
Dim result As DialogResult = dialog.ShowDialog()
If result = DialogResult.OK Then
Dim path As String = dialog.SelectedPath
Dim images As Bitmap() = Me.pdfDocumentViewer1.SaveAsImage(fromPage, toPage)
Dim dictionaryImages As Dictionary(Of [String], Image) = New Dictionary(Of String, Image)()
For i As Integer = 0 To images.Length - 1
Dim name As String = "image" & (i + 1 + fromPage).ToString() & ".bmp"
Dim fileName As String = path & "\" & name
images(i).Save(fileName)
dictionaryImages.Add(fileName, images(i))
Next
Dim message As String = "You have exported " & (fromPage + 1).ToString() & "-" & (toPage + 1).ToString() & " pages as images to:" & vbLf & path
MessageBox.Show(message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information)
Me._formImages = New FormImages()
Me._formImages.DictionaryImages = dictionaryImages
Me._formImages.Show()
End If
End If
End Sub
Display the images in the second Form: FormImages.
[C#]
using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Windows.Forms;
using Spire.PdfViewer.Forms;
namespace pdf2images1
{
public partial class FormImages : Form
{
private Dictionary _dictionaryImags;
public Dictionary DictionaryImages
{
get { return this._dictionaryImags; }
set
{
this._dictionaryImags = value;
this.ViewImages();
}
}
public FormImages()
{
InitializeComponent();
}
public void ViewImages()
{
if (this.DictionaryImages != null && this.DictionaryImages.Count > 0)
{
this.panelImages1.Controls.Clear();
String image_name = "";
int panelHeight = 0;
int panelWidth = 0;
foreach (KeyValuePair pair in this.DictionaryImages)
{
image_name = pair.Key;
Panel panelImage = new Panel();
panelImage.AutoSize = true;
PictureBox ptrBox = new PictureBox();
ptrBox.Height = 150;
ptrBox.Width = 200;
ptrBox.SizeMode = PictureBoxSizeMode.Zoom;
ptrBox.Image = pair.Value;
ptrBox.Cursor = Cursors.Hand;
panelImage.Controls.Add(ptrBox);
LinkLabel lbl = new LinkLabel();
String imageName = Path.GetFileName(pair.Key);
lbl.Text = imageName;
int x = (Int32)(ptrBox.Width / 2 - lbl.Width / 2);
int y = ptrBox.Height;
lbl.Left = x;
lbl.Top = y;
panelImage.Controls.Add(lbl);
this.panelImages1.Controls.Add(panelImage);
this.SetClickEventHandler(ptrBox, lbl, image_name);
panelHeight = panelImage.Height;
panelWidth = panelImage.Width;
}
int nimages = this._dictionaryImags.Count;
if (nimages >= 4)
{
int n = (Int32)Math.Ceiling(Math.Sqrt(nimages));
this.Width = panelWidth * n + 20 * (n - 1) + 40;
this.Height = panelHeight * n + 20 * (n - 1) + 40;
}
}
}
private void SetClickEventHandler(PictureBox ptrBox, LinkLabel lbl, string imageName)
{
ptrBox.Click += new EventHandler(delegate(Object sender, EventArgs args)
{
System.Diagnostics.Process process = new System.Diagnostics.Process();
System.Diagnostics.ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo(imageName);
process.StartInfo = info;
process.Start();
});
lbl.Click += new EventHandler(delegate(Object sender, EventArgs args)
{
System.Diagnostics.Process process = new System.Diagnostics.Process();
System.Diagnostics.ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo(imageName);
process.StartInfo = info;
process.Start();
});
}
}
}
[VB.NET]
Imports System.Collections.Generic Imports System.Drawing Imports System.IO Imports System.Windows.Forms Namespace pdf2images1 Public Partial Class FormImages Inherits Form Private _dictionaryImags As Dictionary(Of [String], Image) Public Property DictionaryImages() As Dictionary(Of [String], Image) Get Return Me._dictionaryImags End Get Set Me._dictionaryImags = value Me.ViewImages() End Set End Property Public Sub New() InitializeComponent() End Sub Public Sub ViewImages() If Me.DictionaryImages IsNot Nothing AndAlso Me.DictionaryImages.Count > 0 Then Me.panelImages1.Controls.Clear() Dim image_name As [String] = "" Dim panelHeight As Integer = 0 Dim panelWidth As Integer = 0 For Each pair As KeyValuePair(Of [String], Image) In Me.DictionaryImages image_name = pair.Key Dim panelImage As New Panel() panelImage.AutoSize = True Dim ptrBox As New PictureBox() ptrBox.Height = 150 ptrBox.Width = 200 ptrBox.SizeMode = PictureBoxSizeMode.Zoom ptrBox.Image = pair.Value ptrBox.Cursor = Cursors.Hand panelImage.Controls.Add(ptrBox) Dim lbl As New LinkLabel() Dim imageName As [String] = Path.GetFileName(pair.Key) lbl.Text = imageName Dim x As Integer = CType(ptrBox.Width \ 2 - lbl.Width \ 2, Int32) Dim y As Integer = ptrBox.Height lbl.Left = x lbl.Top = y panelImage.Controls.Add(lbl) Me.panelImages1.Controls.Add(panelImage) Me.SetClickEventHandler(ptrBox, lbl, image_name) panelHeight = panelImage.Height panelWidth = panelImage.Width Next Dim nimages As Integer = Me._dictionaryImags.Count If nimages >= 4 Then Dim n As Integer = CType(Math.Truncate(Math.Ceiling(Math.Sqrt(nimages))), Int32) Me.Width = panelWidth * n + 20 * (n - 1) + 40 Me.Height = panelHeight * n + 20 * (n - 1) + 40 End If End If End Sub Private Sub SetClickEventHandler(ptrBox As PictureBox, lbl As LinkLabel, imageName As String) AddHandler ptrBox.Click, New EventHandler(Function(sender As [Object], args As EventArgs) Do Dim process As New System.Diagnostics.Process() Dim info As New System.Diagnostics.ProcessStartInfo(imageName) process.StartInfo = info process.Start() End Function) AddHandler lbl.Click, New EventHandler(Function(sender As [Object], args As EventArgs) Do Dim process As New System.Diagnostics.Process() Dim info As New System.Diagnostics.ProcessStartInfo(imageName) process.StartInfo = info process.Start() End Function) End Sub End Class End Namespace
Step 4: Debug the project
Click the Debug or Press F5 to launch the project. You can preview as below.
Export Page 4-7
Display Image 4-7
Export PDF to Image Solution 2
This method is much simple and it needs a Form generated dynamically. Two buttons are provided. One is for exporting the current PDF page, the other is for exporting multiple pages. The difference between the first method and the second lies in you can choose any export range in the first method. For example, you can choose page 4-7 to save as images, but when you use method two, you have to save all the pages from 1-7 since it only support to save page from 1 to current page as images. Please look at the procedure.
Step 1: Create a new project
- Create a new project in Console Application.
- Set the target Framework to be .NET Framework 2 or above.
- Add System. Drawing and Spire.PdfViewer.Forms. dll as references and add the below namespaces at the top of the method.
[C#]
using System; using System.Drawing; using System.IO; using System.Windows.Forms; using Spire.PdfViewer.Forms;
[VB.NET]
Imports System.Drawing Imports System.IO Imports System.Windows.Forms Imports Spire.PdfViewer.Forms
Step 2: Export PDF file pages to images
Load a PDF file from system
[C#]
viewer = new PdfDocumentViewer(); viewer.LoadFromFile(@"D:\michelle\e-iceblue\Spire.PDFViewer\Demos\Data\PDFViewer.pdf");
[VB.NET]
viewer = New PdfDocumentViewer()
viewer.LoadFromFile("D:\michelle\e-iceblue\Spire.PDFViewer\Demos\Data\PDFViewer.pdf")
Create a new Form and design it. Except setting the properties of this Form, two buttons are added also. One is for exporting one page, and the other multiple pages.
[C#]
//form and child components
Form mainForm = new Form();
mainForm.Text = "Spire.PdfView Demo - Export";
mainForm.Size = new System.Drawing.Size(800, 600);
mainForm.StartPosition = FormStartPosition.CenterScreen;
TableLayoutPanel table = new TableLayoutPanel();
table.ColumnCount = 3;
table.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
table.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, 20));
table.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
table.RowCount = 2;
table.RowStyles.Add(new RowStyle(SizeType.Percent, 100));
table.RowStyles.Add(new RowStyle(SizeType.Absolute, 30));
table.Controls.Add(viewer, 0, 0);
table.SetColumnSpan(viewer, 3);
viewer.Dock = DockStyle.Fill;
//Export current page to one image
Button button = new Button();
button.Text = "Export to one image";
button.Size = new Size(180, 24);
button.TextAlign = ContentAlignment.MiddleCenter;
table.Controls.Add(button, 0, 1);
button.Dock = DockStyle.Right;
button.Click += ExportToOneImage;
//Export current pdf document to multiple images
button = new Button();
button.Text = "Export to multiple images";
button.Size = new Size(180, 24);
button.TextAlign = ContentAlignment.MiddleCenter;
table.Controls.Add(button, 2, 1);
button.Dock = DockStyle.Left;
button.Click += ExportToMultipleImages;
mainForm.Controls.Add(table);
table.Dock = DockStyle.Fill;
Application.Run(mainForm);
[VB.NET]
'form and child components Dim mainForm As New Form() mainForm.Text = "Spire.PdfView Demo - Export" mainForm.Size = New System.Drawing.Size(800, 600) mainForm.StartPosition = FormStartPosition.CenterScreen Dim table As New TableLayoutPanel() table.ColumnCount = 3 table.ColumnStyles.Add(New ColumnStyle(SizeType.Percent, 50)) table.ColumnStyles.Add(New ColumnStyle(SizeType.Absolute, 20)) table.ColumnStyles.Add(New ColumnStyle(SizeType.Percent, 50)) table.RowCount = 2 table.RowStyles.Add(New RowStyle(SizeType.Percent, 100)) table.RowStyles.Add(New RowStyle(SizeType.Absolute, 30)) table.Controls.Add(viewer, 0, 0) table.SetColumnSpan(viewer, 3) viewer.Dock = DockStyle.Fill 'Export current page to one image Dim button As New Button() button.Text = "Export to one image" button.Size = New Size(180, 24) button.TextAlign = ContentAlignment.MiddleCenter table.Controls.Add(button, 0, 1) button.Dock = DockStyle.Right AddHandler button.Click, AddressOf ExportToOneImage 'Export current pdf document to multiple images button = New Button() button.Text = "Export to multiple images" button.Size = New Size(180, 24) button.TextAlign = ContentAlignment.MiddleCenter table.Controls.Add(button, 2, 1) button.Dock = DockStyle.Left AddHandler button.Click, AddressOf ExportToMultipleImages mainForm.Controls.Add(table) table.Dock = DockStyle.Fill Application.Run(mainForm)
Save the current PDF page as one image.
[C#]
private static void ExportToOneImage(object sender, EventArgs e)
{
if (viewer.PageCount > 0)
{
SaveFileDialog dialog = new SaveFileDialog();
dialog.Filter = "PNG Format(*.png)|*.png";
if (dialog.ShowDialog() == DialogResult.OK)
{
int currentPage = viewer.CurrentPageNumber;
Bitmap image = viewer.SaveAsImage(currentPage - 1);
image.Save(dialog.FileName);
MessageBox.Show("You have exported current page to an image:\n" + dialog.FileName, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
}
[VB.NET]
Private Shared Sub ExportToOneImage(sender As Object, e As EventArgs)
If viewer.PageCount > 0 Then
Dim dialog As New SaveFileDialog()
dialog.Filter = "PNG Format(*.png)|*.png"
If dialog.ShowDialog() = DialogResult.OK Then
Dim currentPage As Integer = viewer.CurrentPageNumber
Dim image As Bitmap = viewer.SaveAsImage(currentPage - 1)
image.Save(dialog.FileName)
MessageBox.Show("You have exported current page to an image:" & vbLf & dialog.FileName, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information)
End If
End If
End Sub
Save multiple PDF pages to images.
[C#]
private static void ExportToMultipleImages(object sender, EventArgs e)
{
if (viewer.PageCount > 0)
{
FolderBrowserDialog dialog = new FolderBrowserDialog();
if (dialog.ShowDialog() == DialogResult.OK)
{
int currentPage = viewer.CurrentPageNumber;
Bitmap[] images = viewer.SaveAsImage(0, currentPage - 1);
for (int i = 0; i < images.Length; i++)
{
String fileName = Path.Combine(dialog.SelectedPath, String.Format("PDFViewer-{0}.png", i));
images[i].Save(fileName);
}
string message = "You have exported 1" + "-" + currentPage.ToString() + " pages as images to:\n" + dialog.SelectedPath;
MessageBox.Show(message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
}
[VB.NET]
Private Shared Sub ExportToMultipleImages(sender As Object, e As EventArgs)
If viewer.PageCount > 0 Then
Dim dialog As New FolderBrowserDialog()
If dialog.ShowDialog() = DialogResult.OK Then
Dim currentPage As Integer = viewer.CurrentPageNumber
Dim images As Bitmap() = viewer.SaveAsImage(0, currentPage - 1)
For i As Integer = 0 To images.Length - 1
Dim fileName As [String] = Path.Combine(dialog.SelectedPath, [String].Format("PDFViewer-{0}.png", i))
images(i).Save(fileName)
Next
Dim message As String = "You have exported 1" & "-" & currentPage.ToString() & " pages as images to:" & vbLf & dialog.SelectedPath
MessageBox.Show(message, "Spire.PdfViewer Demo", MessageBoxButtons.OK, MessageBoxIcon.Information)
End If
End If
End Sub
Step 3: Debug the project
Press F5 or click Debug to launch the project. Then, preview the effect.
Form
Export Multiple PDF Pages
Obviously, the second method is easier than the first one. But if you have a PDF document with hundreds of pages, solution 1 can exporting the specified pages in a fast speed and, to a large extent, it escapes the trouble of saving numerous PDF pages as images. While, for some PDF file with a few pages, solution 2 is more convenient.
Spire.PDFViewer is a powerful PDF Viewer component performed on .NET and WPF. It enables developers to load PDF document from stream, file and byte array. Also it is available on viewing PDF/A-1B, PDF/X1A and enables to open and read encrypted PDF files Click to know more
