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Operation Event (DocumentViewer)

Summary

Occurs when an operation is invoked inside this document viewer.

Syntax

C++

public event EventHandler<Leadtools.Documents.UI.DocumentViewerOperationEventArgs> Operation

Public Event Operation As EventHandler(Of Leadtools.Documents.UI.DocumentViewerOperationEventArgs)

public:  
   event EventHandler<Leadtools::Documents::UI::DocumentViewerOperationEventArgs^>^ Operation

Remarks

The Operation event occurs anytime the document viewer is performing an operation. Such as when rendering the place holder of a page on the View, when a new annotation object is added, and so forth.

Each Operation event fires twice, first with the value of DocumentViewerOperationEventArgs.IsPostOperation set to false to indicate that the operation is about to happen. Then with DocumentViewerOperationEventArgs.IsPostOperation set to true to indicate that the operation is completed.

The operation type is stored in Operation. When IsPostOperation is false, some operations allow the user to change the behavior or abort the operation.

Refer to Document Viewer Operations for a detailed list of all document viewer operations.

DocumentViewerOperationEventArgs

Example

Start with the example created in DocumentViewer, remove all the code in the Example function and add the code below.

When the user clicks the example button, we will intercept when the user clicks on a link in the page and show a message box.

using Leadtools; 
using Leadtools.Controls; 
using Leadtools.Documents; 
using Leadtools.Documents.UI; 
using Leadtools.Codecs; 
using Leadtools.Caching; 
using Leadtools.Annotations.Core; 
using Leadtools.Forms.Ocr; 
 
// Disable the example button, this should only run once 
exampleButton.Enabled = false; 
_documentViewer.Operation += (sender, e) => 
{ 
   if (e.Operation == DocumentViewerOperation.RunLink && !e.IsPostOperation) 
   { 
      var link = (DocumentLink)e.Data1 ; 
      MessageBox.Show("Linked at specified location clicked and ignored: " + link.Bounds.ToString()); 
      e.Abort = true; 
   } 
};

Imports Leadtools 
Imports Leadtools.Controls 
Imports Leadtools.Documents 
Imports Leadtools.Documents.UI 
Imports Leadtools.Codecs 
Imports Leadtools.Caching 
Imports Leadtools.Annotations.Core 
Imports Leadtools.Forms.Ocr 
 
' Disable the example button, this should only run once 
exampleButton.Enabled = False 
AddHandler _documentViewer.Operation, 
   Sub(sender, e) 
      If e.Operation = DocumentViewerOperation.RunLink AndAlso Not e.IsPostOperation Then 
         Dim link As DocumentLink = CType(e.Data1, DocumentLink) 
         MessageBox.Show("Linked at specified location clicked and ignored: " + link.Bounds.ToString()) 
         e.Abort = True 
      End If 
   End Sub