Loading and Displaying an Image

Take the following steps to start a project and to add some code that loads and displays an image:

Start Visual Studio .NET.
Choose File->New->Project… from the menu.
In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application " in the Templates List.
Type the project name as "Loading and Displaying an Image" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then choose OK .
In the "Solution Explorer" window, right-click on the "References" folder, and select "Add Reference…" from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and browse to Leadtools For .NET "\LEAD Technologies\LEADTOOLS 15\Bin\DotNet\Win32 " folder and select the following DLLs:
- Leadtools.dll
- Leadtools.Codecs.dll
- Leadtools.WinForms.dll
Click the Select button and then press the OK button to add the above DLLs to the application.
Make sure Form1 is in design view. Go to the toolbox (View->Toolbox) and Drag and drop an instance of RasterImageViewer to the form. If you do not have RasterImageViewer in your toolbox, select Tools->Add Remove Toolbox Items from the menu. Click Browse and then select Leadtools.WinForms.DLL from "C:\Program Files\LEAD Technologies\LEADTOOLS 15\Bin\DotNet\Win32" and then click Open and then click OK.
From the toolbox (View->Toolbox), add a Button control (text = "Load").
Switch to Form1 code view (right-click Form1 in the solution explorer then select View Code ) and add the following lines at the beginning of the file: [Visual Basic]
```
Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.WinForms
```
[C#]
```
using Leadtools;
using Leadtools.Codecs;
using Leadtools.WinForms;
```

Add an event handler to the Form1 Load event and add the following code: [Visual Basic]


' the RasterCodecs object for loading/saving images
Private codecs As RasterCodecs

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
   ' Initialize a new RasterCodecs object
   RasterCodecs.Startup()
   codecs = New RasterCodecs()
End Sub

[C#]

 
// the RasterCodecs object for loading/saving images
private RasterCodecs codecs;

private void Form1_Load(object sender, System.EventArgs e)
{
   // Initialize a new RasterCodecs object
   RasterCodecs.Startup();
   codecs = new RasterCodecs();
}

Add an event handler to the Form1 FormClosing event and add the following code: [Visual Basic]


Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As FormClosingEventArgs) Handles MyBase.FormClosing
   RasterCodecs.Shutdown()
End Sub

[C#]


private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
   RasterCodecs.Shutdown();
}

Double-click the button1 Button on the form to add the event handler for it and add the following code: [Visual Basic]


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
   ' show the open file dialog
   Dim dlg As New OpenFileDialog
   dlg.Filter = "All Files|*.*"
   If (dlg.ShowDialog(Me) = DialogResult.OK) Then
      Try
         ' try to load the file
         Dim tempImage As RasterImage = codecs.Load(dlg.FileName)
         
         ' set the image into the viewer
         RasterImageViewer1.Image = tempImage
      Catch ex As Exception
         MessageBox.Show(Me, ex.Message)
      End Try
   End If
End Sub

[C#]


private void button1_Click(object sender, System.EventArgs e)
{
   // show the open file dialog
   OpenFileDialog dlg = new OpenFileDialog();
   dlg.Filter = "All Files|*.*";
   if(dlg.ShowDialog(this) == DialogResult.OK)
   {
      try
      {
         // try to load the file
         RasterImage tempImage = codecs.Load(dlg.FileName);
         
         // set the image into the viewer
         rasterImageViewer1.Image = tempImage;
      }
      catch(Exception ex)
      {
         MessageBox.Show(this, ex.Message);
      }
   }
}

Build, and Run the program to test it.

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Loading and Displaying an Image