IResourceSavingCallback Interface

Implement this interface if you want to control how Aspose.Words saves external resources (images, fonts and css) when saving a document to fixed page HTML or SVG.

Namespace:  Aspose.Words.Saving
Assembly:  Aspose.Words (in Aspose.Words.dll) Version: 21.5.0

ExpandedSyntax

public interface IResourceSavingCallback

The IResourceSavingCallback type exposes the following members.

ExpandedMethods

  NameDescription
Public methodCode exampleResourceSaving
Called when Aspose.Words saves an external resource to fixed page HTML or SVG formats.

ExpandedExamples

Shows how to use a callback to track external resources created while converting a document to HTML.
public void ResourceSavingCallback()
{
    Document doc = new Document(MyDir + "Bullet points with alternative font.docx");

    FontSavingCallback callback = new FontSavingCallback();

    HtmlFixedSaveOptions saveOptions = new HtmlFixedSaveOptions
    {
        ResourceSavingCallback = callback
    };

    doc.Save(ArtifactsDir + "HtmlFixedSaveOptions.UsingMachineFonts.html", saveOptions);

    Console.WriteLine(callback.GetText());
}

private class FontSavingCallback : IResourceSavingCallback
{
    /// <summary>
    /// Called when Aspose.Words saves an external resource to fixed page HTML or SVG.
    /// </summary>
    public void ResourceSaving(ResourceSavingArgs args)
    {
        mText.AppendLine($"Original document URI:\t{args.Document.OriginalFileName}");
        mText.AppendLine($"Resource being saved:\t{args.ResourceFileName}");
        mText.AppendLine($"Full uri after saving:\t{args.ResourceFileUri}\n");
    }

    public string GetText()
    {
        return mText.ToString();
    }

    private readonly StringBuilder mText = new StringBuilder();
}
Shows how to use a callback to print the URIs of external resources created while converting a document to HTML.
public void HtmlFixedResourceFolder()
{
    Document doc = new Document(MyDir + "Rendering.docx");

    ResourceUriPrinter callback = new ResourceUriPrinter();

    HtmlFixedSaveOptions options = new HtmlFixedSaveOptions
    {
        SaveFormat = SaveFormat.HtmlFixed,
        ExportEmbeddedImages = false,
        ResourcesFolder = ArtifactsDir + "HtmlFixedResourceFolder",
        ResourcesFolderAlias = ArtifactsDir + "HtmlFixedResourceFolderAlias",
        ShowPageBorder = false,
        ResourceSavingCallback = callback
    };

    // A folder specified by ResourcesFolderAlias will contain the resources instead of ResourcesFolder.
    // We must ensure the folder exists before the streams can put their resources into it.
    Directory.CreateDirectory(options.ResourcesFolderAlias);

    doc.Save(ArtifactsDir + "HtmlFixedSaveOptions.HtmlFixedResourceFolder.html", options);

    Console.WriteLine(callback.GetText());

    string[] resourceFiles = Directory.GetFiles(ArtifactsDir + "HtmlFixedResourceFolderAlias");

    Assert.False(Directory.Exists(ArtifactsDir + "HtmlFixedResourceFolder"));
    Assert.AreEqual(6, resourceFiles.Count(f => f.EndsWith(".jpeg") || f.EndsWith(".png") || f.EndsWith(".css")));
}

/// <summary>
/// Counts and prints URIs of resources contained by as they are converted to fixed HTML.
/// </summary>
private class ResourceUriPrinter : IResourceSavingCallback
{
    void IResourceSavingCallback.ResourceSaving(ResourceSavingArgs args)
    {
        // If we set a folder alias in the SaveOptions object, we will be able to print it from here.
        mText.AppendLine($"Resource #{++mSavedResourceCount} \"{args.ResourceFileName}\"");

        string extension = Path.GetExtension(args.ResourceFileName);
        switch (extension)
        {
            case ".ttf":
            case ".woff":
            {
                // By default, 'ResourceFileUri' uses system folder for fonts.
                // To avoid problems in other platforms you must explicitly specify the path for the fonts.
                args.ResourceFileUri = ArtifactsDir + Path.DirectorySeparatorChar + args.ResourceFileName;
                break;
            }
        }

        mText.AppendLine("\t" + args.ResourceFileUri);

        // If we have specified a folder in the "ResourcesFolderAlias" property,
        // we will also need to redirect each stream to put its resource in that folder.
        args.ResourceStream = new FileStream(args.ResourceFileUri, FileMode.Create);
        args.KeepResourceStreamOpen = false;
    }

    public string GetText()
    {
        return mText.ToString();
    }

    private int mSavedResourceCount;
    private readonly StringBuilder mText = new StringBuilder();
}

ExpandedSee Also