Load and Save Progress Reporting and Cancellation

With GemBox.Document you can track the progress of long-running operations like loading and saving large documents, and you have the option to cancel them. Currently, the supported operations are loading DOCX files and saving DOCX, PDF, and image files. You can track the operations by handling the DocxLoadOptions.ProgressChanged, DocxSaveOptions.ProgressChanged, PdfSaveOptions.ProgressChanged, and ImageSaveOptions.ProgressChanged events.

The following example is a simple console application that shows the save progress of a large document.

The progress reported with GemBox.Document
Screenshot of the progress reported with GemBox.Document
View on GitHub 
using GemBox.Document;
using System;

class Program
{
    static void Main()
    {
        // If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");

        Console.WriteLine("Creating document");

        // Create large document.
        var document = new DocumentModel();
        var section = new Section(document);
        document.Sections.Add(section);
        for (var i = 0; i < 10000; i++)
            section.Blocks.Add(new Paragraph(document, i.ToString()));

        // Create save options.
        var saveOptions = new DocxSaveOptions();
        saveOptions.ProgressChanged += (eventSender, args) =>
        {
            Console.WriteLine($"Progress changed - {args.ProgressPercentage}%");
        };

        // Save document.
        document.Save("document.docx", saveOptions);
    }
}

Imports GemBox.Document
Imports System

Module Program

    Sub Main()

        ' If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY")

        Console.WriteLine("Creating document")

        ' Create large document.
        Dim document As New DocumentModel()
        Dim section As New Section(document)
        document.Sections.Add(section)
        For i As Integer = 0 To 10000
            section.Blocks.Add(New Paragraph(document, i.ToString()))
        Next

        ' Create save options.
        Dim saveOptions = New DocxSaveOptions()
        AddHandler saveOptions.ProgressChanged,
            Sub(eventSender, args)
                Console.WriteLine($"Progress changed - {args.ProgressPercentage}%")
            End Sub

        ' Save document.
        document.Save("document.docx", saveOptions)

    End Sub

End Module

Progress reporting in WPF

The ProgressChanged event is fired on the same thread that started the operation. Therefore, if the operation starts in the UI thread of a WPF application, the thread will be blocked. Because of that, the application won't show the changes made as a response to the fired event.

The following example shows how to use Tasks to run the load operation on a new thread and how to use the SynchronizationContext to make changes to the progress bar on the UI thread.

The progress reported in WPF with GemBox.Document
Screenshot of the progress reported in WPF with GemBox.Document
View on GitHub 
<Window x:Class="MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Progress reporting in WPF" Height="150" Width="300">
    <Grid>
        <ProgressBar HorizontalAlignment="Left" Height="32" Margin="27,73,0,0" VerticalAlignment="Top" Width="200" Name="progressBar"/>
        <Button x:Name="button" Content="Load" HorizontalAlignment="Left" Margin="27,19,0,0" VerticalAlignment="Top" Width="236" Height="36" Click="loadButton_Click"/>
        <Label x:Name="percentageLabel" Content="" HorizontalAlignment="Left" Margin="239,77,0,0" VerticalAlignment="Top" RenderTransformOrigin="0.867,0.59"/>
    </Grid>
</Window>
using GemBox.Document;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;

public partial class MainWindow : Window
{
    public MainWindow()
    {
        // If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");
        InitializeComponent();
    }

    private async void loadButton_Click(object sender, RoutedEventArgs e)
    {
        // Capture the current context on the UI thread.
        var context = SynchronizationContext.Current;

        // Create load options.
        var loadOptions = new DocxLoadOptions();
        loadOptions.ProgressChanged += (eventSender, args) =>
        {
            var percentage = args.ProgressPercentage;
            // Invoke on the UI thread.
            context.Post(progressPercentage =>
            {
                // Update UI.
                this.progressBar.Value = (int)progressPercentage;
                this.percentageLabel.Content = progressPercentage.ToString() + "%";
            }, percentage);
        };

        this.percentageLabel.Content = "0%";
        // Use tasks to run the load operation in a new thread.
        var file = await Task.Run(() => DocumentModel.Load("%#LargeDocument.docx%", loadOptions));
    }
}

Imports GemBox.Document
Imports System.Threading
Imports System.Threading.Tasks
Imports System.Windows

Class MainWindow

    Public Sub New()
        ' If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY")
        InitializeComponent()
    End Sub

    Private Async Sub loadButton_Click(sender As Object, e As RoutedEventArgs)
        ' Capture the current context on the UI thread.
        Dim context = SynchronizationContext.Current

        ' Create load options.
        Dim loadOptions = New DocxLoadOptions()
        AddHandler loadOptions.ProgressChanged,
            Sub(eventSender, args)
                Dim percentage = args.ProgressPercentage
                ' Invoke on the UI thread.
                context.Post(
                    Sub(progressPercentage)
                        ' Update UI.
                        Me.progressBar.Value = CType(progressPercentage, Integer)
                        Me.percentageLabel.Content = progressPercentage.ToString() & "%"
                    End Sub, percentage)
            End Sub

        Me.percentageLabel.Content = "0%"
        ' Use tasks to run the load operation in a new thread.
        Await Task.Run(
            Sub()
                DocumentModel.Load("%#LargeDocument.docx%", loadOptions)
            End Sub)
    End Sub

End Class

Progress reporting in Windows Forms

Similarly to WPF, to show the progress of an operation in the UI, it is necessary to run the process on a separate thread and report the changes on the UI thread.

The example below shows how to display the progress of a load operation in the progress bar.

The progress reported in Windows Forms with GemBox.Document
Screenshot of the progress reported in Windows Forms with GemBox.Document
View on GitHub 
using GemBox.Document;
using System;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

public partial class MainForm : Form
{
    public MainForm()
    {
        // If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");
        InitializeComponent();
    }

    private async void loadButton_Click(object sender, EventArgs e)
    {
        // Capture the current context on the UI thread.
        var context = SynchronizationContext.Current;

        // Create load options.
        var loadOptions = new DocxLoadOptions();
        loadOptions.ProgressChanged += (eventSender, args) =>
        {
            var percentage = args.ProgressPercentage;
            // Invoke on the UI thread.
            context.Post(progressPercentage =>
            {
                // Update UI.
                this.progressBar.Value = (int)progressPercentage;
                this.percentageLabel.Text = progressPercentage.ToString() + "%";
            }, percentage);
        };

        this.percentageLabel.Text = "0%";
        // Use tasks to run the load operation in a new thread.
        var file = await Task.Run(() => DocumentModel.Load("%#LargeDocument.docx%", loadOptions));
    }
}

Imports GemBox.Document
Imports System
Imports System.Threading
Imports System.Threading.Tasks
Imports System.Windows.Forms

Public Class MainForm

    Public Sub New()
        ' If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY")
        InitializeComponent()
    End Sub

    Private Async Sub LoadButton_Click(sender As Object, e As EventArgs) Handles LoadButton.Click
        ' Capture the current context on the UI thread.
        Dim context = SynchronizationContext.Current

        ' Create load options.
        Dim loadOptions = New DocxLoadOptions()
        AddHandler loadOptions.ProgressChanged,
            Sub(eventSender, args)
                Dim percentage = args.ProgressPercentage
                ' Invoke on the UI thread.
                context.Post(
                    Sub(progressPercentage)
                        ' Update UI.
                        Me.ProgressBar.Value = CType(progressPercentage, Integer)
                        Me.PercentageLabel.Text = progressPercentage.ToString() & "%"
                    End Sub, percentage)
            End Sub

        Me.PercentageLabel.Text = "0%"
        ' Use tasks to run the load operation in a new thread.
        Await Task.Run(
            Sub()
                DocumentModel.Load("%#LargeDocument.docx%", loadOptions)
            End Sub)
    End Sub

End Class

Cancellation

By handling the ProgressChanged event in SaveOptions or LoadOptions, GemBox.Document gives you the ability to cancel the ongoing operation.

The following example shows how to cancel the saving of a document in a console application after a specific time.

View on GitHub 
using GemBox.Document;
using System;
using System.Diagnostics;

class Program
{
    static void Main()
    {
        // If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");

        // Create document.
        var document = new DocumentModel();
        var section = new Section(document);
        document.Sections.Add(section);
        for (var i = 0; i < 10000; i++)
            section.Blocks.Add(new Paragraph(document, i.ToString()));

        var stopwatch = new Stopwatch();
        stopwatch.Start();

        // Create save options.
        var saveOptions = new DocxSaveOptions();
        saveOptions.ProgressChanged += (sender, args) =>
        {
            // Cancel operation after five seconds.
            if (stopwatch.Elapsed.Seconds >= 5)
                args.CancelOperation();
        };

        try
        {
            document.Save("Cancellation.docx", saveOptions);
            Console.WriteLine("Operation fully finished");
        }
        catch (OperationCanceledException)
        {
            Console.WriteLine("Operation was cancelled");
        }
    }
}

Imports GemBox.Document
Imports System
Imports System.Diagnostics

Module Program

    Sub Main()

        ' If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY")

        ' Create document.
        Dim document As New DocumentModel()
        Dim section As New Section(document)
        document.Sections.Add(section)
        For i As Integer = 0 To 10000
            section.Blocks.Add(New Paragraph(document, i.ToString()))
        Next

        Dim stopwatch = New Stopwatch()
        stopwatch.Start()

        ' Create save options.
        Dim saveOptions = New DocxSaveOptions()
        AddHandler saveOptions.ProgressChanged,
            Sub(eventSender, args)
                ' Cancel operation after five seconds.
                If stopwatch.Elapsed.Seconds >= 5 Then
                    args.CancelOperation()
                End If
            End Sub

        Try
            document.Save("Cancellation.docx", saveOptions)
            Console.WriteLine("Operation fully finished")
        Catch ex As OperationCanceledException
            Console.WriteLine("Operation was cancelled")
        End Try

    End Sub

End Module

Cancellation in WPF

The example below shows how to implement a button in WPF that cancels the load operation.

Cancellation in WPF with GemBox.Document
Screenshot of cancelled operation in WPF with GemBox.Document
View on GitHub 
<Window x:Class="MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Cancellation in WPF" Height="200" Width="350">
    <Grid>
        <Button x:Name="loadButton" Content="Start Loading" HorizontalAlignment="Left" Margin="57,31,0,0" VerticalAlignment="Top" Width="228" Height="31" Click="loadButton_Click" />
        <Button x:Name="cancelButton" Content="Cancel" HorizontalAlignment="Left" Margin="57,111,0,0" VerticalAlignment="Top" Width="228" Height="32" Click="cancelButton_Click" />
        <ProgressBar HorizontalAlignment="Left" Height="25" Margin="57,73,0,0" VerticalAlignment="Top" Width="228" Name="progressBar" />
    </Grid>
</Window>
using GemBox.Document;
using System;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;

public partial class MainWindow : Window
{
    private volatile bool cancellationRequested;

    public MainWindow()
    {
        // If using the Professional version, put your serial key below
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");
        InitializeComponent();
    }

    private async void loadButton_Click(object sender, RoutedEventArgs e)
    {
        // Capture the current context on the UI thread.
        var context = SynchronizationContext.Current;

        var loadOptions = new DocxLoadOptions();
        loadOptions.ProgressChanged += (eventSender, args) =>
        {
            // Show progress.
            context.Post(progressPercentage => this.progressBar.Value = (int)progressPercentage, args.ProgressPercentage);

            // Cancel if requested.
            if (this.cancellationRequested)
                args.CancelOperation();
        };

        try
        {
            var file = await Task.Run(() => DocumentModel.Load("%#LargeDocument.docx%", loadOptions));
        }
        catch (OperationCanceledException)
        {
            // Operation cancelled.
        }
    }

    private void cancelButton_Click(object sender, RoutedEventArgs e)
    {
        this.cancellationRequested = true;
    }
}

Imports GemBox.Document
Imports System
Imports System.Threading
Imports System.Threading.Tasks
Imports System.Windows

Class MainWindow

    Private Property cancellationRequested As Boolean

    Public Sub New()
        ' If using the Professional version, put your serial key below.
        ComponentInfo.SetLicense("FREE-LIMITED-KEY")
        InitializeComponent()
    End Sub

    Private Async Sub loadButton_Click(sender As Object, e As RoutedEventArgs) Handles loadButton.Click
        ' Capture the current context on the UI thread.
        Dim context = SynchronizationContext.Current

        ' Create load options.
        Dim loadOptions = New DocxLoadOptions()
        AddHandler loadOptions.ProgressChanged,
            Sub(eventSender, args)
                ' Show progress.
                context.Post(
                    Sub(progressPercentage)
                        Me.progressBar.Value = CType(progressPercentage, Integer)
                    End Sub, args.ProgressPercentage)

                ' Cancel if requested.
                If Me.cancellationRequested Then
                    args.CancelOperation()
                End If
            End Sub

        Try
            Dim file = Await Threading.Tasks.Task.Run(
                Function() As DocumentModel
                    Return DocumentModel.Load("%#LargeDocument.docx%", loadOptions)
                End Function)
        Catch ex As OperationCanceledException
            ' Operation cancelled.
        End Try
    End Sub

    Private Sub cancelButton_Click(sender As Object, e As RoutedEventArgs) Handles cancelButton.Click
        Me.cancellationRequested = True
    End Sub

End Class

See also

Open and read Word files from C# / VB.NET applications

Open and read Word files from C# / VB.NET applications

Create and write Word files of DOCX format from C# / VB.NET applications

Create and write Word files of DOCX format from C# / VB.NET applications

Right-to-Left Text | GemBox.Document Example

Right-to-Left Text | GemBox.Document Example

Next steps

GemBox.Document is a .NET component that enables you to read, write, edit, convert, and print document files from your .NET applications using one simple API. How about testing it today?

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