IResourceLoadingCallback

IResourceLoadingCallback interface

Implement this interface if you want to control how Aspose.Words loads external resource when importing a document and inserting images using DocumentBuilder.

public interface IResourceLoadingCallback

Methods

Name Description
ResourceLoading(ResourceLoadingArgs) Called when Aspose.Words loads any external resource.

Examples

Shows how to customize the process of loading external resources into a document.

{
    Document doc = new Document();
    doc.ResourceLoadingCallback = new ImageNameHandler();

    DocumentBuilder builder = new DocumentBuilder(doc);

    // Images usually are inserted using a URI, or a byte array.
    // Every instance of a resource load will call our callback's ResourceLoading method.
    builder.InsertImage("Google logo");
    builder.InsertImage("Aspose logo");
    builder.InsertImage("Watermark");

    Assert.AreEqual(3, doc.GetChildNodes(NodeType.Shape, true).Count);

    doc.Save(ArtifactsDir + "DocumentBase.ResourceLoadingCallback.docx");

/// <summary>
/// Allows us to load images into a document using predefined shorthands, as opposed to URIs.
/// This will separate image loading logic from the rest of the document construction.
/// </summary>
private class ImageNameHandler : IResourceLoadingCallback
{
    public ResourceLoadingAction ResourceLoading(ResourceLoadingArgs args)
    {
        // If this callback encounters one of the image shorthands while loading an image,
        // it will apply unique logic for each defined shorthand instead of treating it as a URI.
        if (args.ResourceType == ResourceType.Image)
            switch (args.OriginalUri)
            {
                case "Google logo":
                    using (WebClient webClient = new WebClient())
                    {
                        args.SetData(webClient.DownloadData("http://www.google.com/images/logos/ps_logo2.png"));
                    }

                    return ResourceLoadingAction.UserProvided;

                case "Aspose logo":
                    args.SetData(File.ReadAllBytes(ImageDir + "Logo.jpg"));

                    return ResourceLoadingAction.UserProvided;

                case "Watermark":
                    args.SetData(File.ReadAllBytes(ImageDir + "Transparent background logo.png"));

                    return ResourceLoadingAction.UserProvided;
            }

        return ResourceLoadingAction.Default;
    }
}

See Also