Using the TiledImageViewer control on the server side.

Take the following steps to create a project that uses features of the LEADTOOLS TiledImageViewer Web Control from the server side:

Start Visual Studio 2005.
Choose File->New->Web Site… from the menu.
In the New Web Site dialog box, choose "ASP.NET Web Site" in the Templates List, and choose either "Visual C#" or "Visual Basic" in the Language drop-down list box.
In the Location drop-down list box choose "File System", enter “C:\Inetpub\wwwroot\UsingTiledImageViewer_Server” into the Project Name field, and click OK.
If desired, type a new location for your project or select a directory by clicking the Browse button and then browsing to the correct directory and then click OK.
Repeat the previous step except in the Add Reference dialog box select the Browse tab and browse to the C:\Program Files\LEAD Technologies\LEADTOOLS 15\Bin\Dotnet\Win32" folder and select the following DLL:
- Leadtools.Web.dll.
Now click OK to close the Add Reference dialog box.
In the Solution Explorer pane, right-click on the "Default.aspx" file and choose "View Designer" from the context menu.
Go to the toolbox (View->Toolbox) and drag and drop an instance of TiledImageViewer onto the web form. If you do not have the TiledImageViewer in your toolbox, select "Tools->Choose Toolbox Items..." from the menu. Click Browse and then select "Leadtools.Web.dll" from the "C:\Program Files\LEAD Technologies\LEADTOOLS 15\Bin\Dotnet\Win32" folder. Click Open and then OK.
Go to the toolbox (View-Toolbox) and from the Standard tab drag and drop 5 Labels, 5 Buttons, 1 Text Box, and 4 drop-down list boxes onto the web form.

Change the properties of the dropped controls as follows:

Control	Property	New Value
Label1	ID Text	_lblImageUrl Image Url
TextBox1	ID	_tbImageUrl
Button1	ID Text	_btnViewImage View Image
Label2	ID Text	_lblSizeMode SizeMode
DropDownList1	ID AutoPostBack	_ddlSizeMode True
Label3	ID Text	_lblScaleFactor ScaleFactor
DropDownList2	ID AutoPostBack	_ddlScaleFactor True
Label4	ID Text	_lblHorizontalAlignMode HorizontalAlignMode
DropDownList3	ID AutoPostBack	_ddlHorizontalAlignMode True
Label5	ID Text	_lblVerticalAlignMode VerticalAlignMode
DropDownList4	ID AutoPostBack	_ddlVerticalAlignMode True
Button2	ID Text	_btnScrollUp Up
Button3	ID Text	_btnScrollLeft Left
Button4	ID Text	_btnScrollRight Right
Button5	ID Text	_btnScrollDown Down

Switch to the "Default.aspx" code view (right-click default.aspx in the Solution Explorer and then select "View Code") and add the following lines at the beginning of the file:
Visual Basic
```
Imports System.Drawing

Imports Leadtools.Web.Controls
```
C#
```
using System.Drawing

using Leadtools.Web.Controls;
```

Update the Page_Load event handler to be as follows:

Visual Basic


Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
  If (Not IsPostBack) Then
     ' Initialize the ImageViewer control.
     TiledImageViewer1.ResourcesPath = "Resources"
     ' Hide the scroll bars
     TiledImageViewer1.ScrollBarVisible = False

     ' Fill in the Combo Boxes
     BindDropDownListToEnum(_ddlSizeMode, GetType(ImageViewerSizeMode), TiledImageViewer1.SizeMode)
     BindDropDownListToEnum(_ddlHorizontalAlignMode, GetType(ImageViewerAlignMode), TiledImageViewer1.HorizontalAlignMode)
     BindDropDownListToEnum(_ddlVerticalAlignMode, GetType(ImageViewerAlignMode), TiledImageViewer1.VerticalAlignMode)
     Dim scaleFactors() As Integer = {1000, 800, 600, 400, 200, 100, 75, 50, 25, 10}
     Dim factor1 As Integer = CInt(TiledImageViewer1.ScaleFactor)
     For i As Integer = 0 To scaleFactors.Length - 1
        _ddlScaleFactor.Items.Add(scaleFactors(i).ToString())
        If (factor1 = scaleFactors(i)) Then
           _ddlScaleFactor.SelectedIndex = i
        End If
     Next
  End If
End Sub


protected void Page_Load(object sender, EventArgs e)
{
   if(!IsPostBack)
   {
      // Initialize the ImageViewer control.
      ImageViewer1.ResourcesPath = "Resources";
      // Hide the scroll bars
      TiledImageViewer1.ScrollBarVisible = false;
      // Fill in the Combo Boxes
      BindDropDownListToEnum(_ddlSizeMode, typeof(ImageViewerSizeMode), ImageViewer1.SizeMode);
      BindDropDownListToEnum(_ddlHorizontalAlignMode, typeof(ImageViewerAlignMode), ImageViewer1.HorizontalAlignMode);
      BindDropDownListToEnum(_ddlVerticalAlignMode, typeof(ImageViewerAlignMode), ImageViewer1.VerticalAlignMode);
   
      int[] scaleFactors = { 1000, 800, 600, 400, 200, 100, 75, 50, 25, 10 };
      int factor1 = (int)(ImageViewer1.ScaleFactor);
      for(int i = 0; i < scaleFactors.Length; i++)
      {
         _ddlScaleFactor.Items.Add(scaleFactors[i].ToString());
         if(factor1 == scaleFactors[i])
            _ddlScaleFactor.SelectedIndex = i;
      }
   }
}

double click on _btnViewImage, _ddlSizeMode, _ddlScaleFactor, _ddlHorizontalAlignMode _ddlVerticalAlignMode, _btnScrollUp, _btnScrollLeft, _btnScrollRight, _btnScrollDown controls and Update the event handlers as follows:

Visual Basic


Protected Sub _btnViewImage_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _btnViewImage.Click
   TiledImageViewer1.ImageUrl = _tbImageUrl.Text
End Sub
Protected Sub _ddlSizeMode_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _ddlSizeMode.SelectedIndexChanged
   TiledImageViewer1.SizeMode = GetDropDownListSelectedItem(_ddlSizeMode, GetType(ImageViewerSizeMode))
End Sub
Protected Sub _ddlScaleFactor_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _ddlScaleFactor.SelectedIndexChanged
   TiledImageViewer1.ScaleFactor = Convert.ToInt32(_ddlScaleFactor.SelectedItem.Value)
End Sub
Protected Sub _ddlHorizontalAlignMode_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _ddlHorizontalAlignMode.SelectedIndexChanged
   TiledImageViewer1.HorizontalAlignMode = GetDropDownListSelectedItem(_ddlHorizontalAlignMode, GetType(ImageViewerAlignMode))
End Sub
Protected Sub _ddlVerticalAlignMode_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _ddlVerticalAlignMode.SelectedIndexChanged
   TiledImageViewer1.VerticalAlignMode = GetDropDownListSelectedItem(_ddlVerticalAlignMode, GetType(ImageViewerAlignMode))
End Sub
Protected Sub _btnScrollLeft_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _btnScrollLeft.Click
   Dim x As Integer = TiledImageViewer1.ScrollPosition.X - 10
   If x < 0 Then
      x = -TiledImageViewer1.ScrollPosition.X
   End If

   TiledImageViewer1.ScrollPosition = New System.Drawing.Point(x, TiledImageViewer1.ScrollPosition.Y)
End Sub

Protected Sub _btnScrollUp_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _btnScrollUp.Click
   Dim y As Integer = TiledImageViewer1.ScrollPosition.Y - 10
   If y < 0 Then
      y = -TiledImageViewer1.ScrollPosition.Y
   End If

   TiledImageViewer1.ScrollPosition = New System.Drawing.Point(TiledImageViewer1.ScrollPosition.X, y)
End Sub

Protected Sub _btnScrollDown_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _btnScrollDown.Click
   TiledImageViewer1.ScrollPosition = New System.Drawing.Point(TiledImageViewer1.ScrollPosition.X, TiledImageViewer1.ScrollPosition.Y + 10)
End Sub

Protected Sub _btnScrollRight_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _btnScrollRight.Click
   TiledImageViewer1.ScrollPosition = New System.Drawing.Point(TiledImageViewer1.ScrollPosition.X + 10, TiledImageViewer1.ScrollPosition.Y)
End Sub


protected void _btnViewImage_Click(object sender, EventArgs e)
{
   ImageViewer1.ImageSize = new Size(Convert.ToInt32(_tbImageWidth.Text), Convert.ToInt32(_tbImageHeight.Text));
   ImageViewer1.ImageUrl = _tbImageUrl.Text;
}
protected void _ddlSizeMode_SelectedIndexChanged(object sender, EventArgs e)
{
  ImageViewer1.SizeMode = (ImageViewerSizeMode)GetDropDownListSelectedItem(_ddlSizeMode, typeof(ImageViewerSizeMode));
}
protected void _ddlScaleFactor_SelectedIndexChanged(object sender, EventArgs e)
{
  ImageViewer1.ScaleFactor = Convert.ToInt32(_ddlScaleFactor.SelectedItem.Value);
}
protected void _ddlHorizontalAlignMode_SelectedIndexChanged(object sender, EventArgs e)
{
  ImageViewer1.HorizontalAlignMode = (ImageViewerAlignMode)GetDropDownListSelectedItem(_ddlHorizontalAlignMode, typeof(ImageViewerAlignMode));
}
protected void _ddlVerticalAlignMode_SelectedIndexChanged(object sender, EventArgs e)
{
  ImageViewer1.VerticalAlignMode = (ImageViewerAlignMode)GetDropDownListSelectedItem(_ddlVerticalAlignMode, typeof(ImageViewerAlignMode));
}
protected void _btnScrollUp_Click(object sender, EventArgs e)
{
   int y = (TiledImageViewer1.ScrollPosition.Y - 10 > 0) ? TiledImageViewer1.ScrollPosition.Y - 10 : -TiledImageViewer1.ScrollPosition.Y;
   TiledImageViewer1.ScrollPosition = new System.Drawing.Point(TiledImageViewer1.ScrollPosition.X, y);
}
protected void _btnScrollLeft_Click(object sender, EventArgs e)
{
   int x = (TiledImageViewer1.ScrollPosition.X - 10 > 0) ? TiledImageViewer1.ScrollPosition.X - 10 : -TiledImageViewer1.ScrollPosition.X;
   TiledImageViewer1.ScrollPosition = new System.Drawing.Point(x, TiledImageViewer1.ScrollPosition.Y);
}
protected void _btnScrollRight_Click(object sender, EventArgs e)
{
   TiledImageViewer1.ScrollPosition = new System.Drawing.Point(TiledImageViewer1.ScrollPosition.X + 10, TiledImageViewer1.ScrollPosition.Y);
}
protected void _btnScrollDown_Click(object sender, EventArgs e)
{
   TiledImageViewer1.ScrollPosition = new System.Drawing.Point(TiledImageViewer1.ScrollPosition.X, TiledImageViewer1.ScrollPosition.Y + 10);
}

Add the following functions to the end of "Default.aspx.cs" file (for C#) or before the "End Class" statement (for Visual Basic):

Visual Basic


Private Sub BindDropDownListToEnum(ByVal ddl As DropDownList, ByVal t As Type, ByVal selected As Object)
   Dim a As Array = [Enum].GetValues(t)
   ddl.DataSource = a
   ddl.DataBind()
   Dim selectedValue As String = selected.ToString()
   For i As Integer = 0 To ddl.Items.Count - 1
      If (ddl.Items(i).Value = selectedValue) Then
         ddl.SelectedIndex = i
         Return
      End If
   Next
End Sub
Private Function GetDropDownListSelectedItem(ByVal ddl As DropDownList, ByVal t As Type) As Object
   Return [Enum].Parse(t, ddl.SelectedItem.Value)
End Function


private void BindDropDownListToEnum(DropDownList ddl, Type t, object selected)
{
   Array a = Enum.GetValues(t);
   ddl.DataSource = a;
   ddl.DataBind();
   string selectedValue = selected.ToString();
   for(int i = 0; i < ddl.Items.Count; i++)
   {
      if(ddl.Items[i].Value == selectedValue)
      {
         ddl.SelectedIndex = i;
         return;
      }
   }
}
private object GetDropDownListSelectedItem(DropDownList ddl, Type t)
{
   return Enum.Parse(t, ddl.SelectedItem.Value);
}

Your web.config file has to tell the server how to handle the Leadtools.Web.Handlers.ImageInformation and the Leadtools.Web.Handlers.ImageGenerator requests.
Drilling down through the file's schema, you will need to add the httpHandlers section inside the <system.web> </system.web> tag (if it is not already there), so that it looks like the following:
```
<httpHandlers>
   <add verb="*" path="*.leadinfo" type="Leadtools.Web.Handlers.ImageInformation, Leadtools.Web"/>
   <add verb="*" path="*.leadgen" type="Leadtools.Web.Handlers.ImageGenerator, Leadtools.Web"/>
</httpHandlers>
```
Also you have to set up the IIS to handle the requests for ".leadinfo" and ".leadgen".
In your Site's properties dialog box, click the Home Directory tab and click Configuration.
When the Application Configuration dialog box appears, click Add. When the Add/Edit Application Extension Mapping dialog box appears, click Browse and browse to the path of the "aspnet_isapi.dll" (you can find it in "C:\Windows\Microsoft.NET\Framework\v2.0.50727" folder) to fill the Executable edit box. Enter ".leadinfo" into the Extension edit box.
Now click OK, and repeat the last step except enter ".leadgen" into the Extension edit box. Click OK in each open dialog to close the three dialogs.
From the "C:\Program Files\LEAD Technologies\LEADTOOLS 15\Bin\Dotnet\Win32" folder, copy any filter codecs you want to work with to the project's Bin folder: Leadtools.Codecs.J2k, Leadtools.Codecs.Gif, Leadtools.Tif, Leadtools.Codecs.Cmp, ...etc.
Inside the project folder create a folder named "Resources" and copy all of the java script files and images found in the "C:\Program Files\LEAD Technologies\LEADTOOLS 15\Examples\DotNet\Resources\Web" folder to this new folder.
Run the project and play with it as follows:
1. Type a path to a supported format (gif, bmp, png, jpeg, tif, cmp, ...etc) in the ImageUrl TextBox.
2. Click the ViewImage to load the image into the TiledImageViewer control.
3. Change the selections in the drop-down list boxes and notice the differences in the displayed image.
4. Click the Left, Right, Up and Down buttons to scroll the image manually.

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Using the TiledImageViewer control on the server side.