Events in Blazor PDF Viewer Component

1 Mar 202311 minutes to read

The events provided in PDF Viewer component are listed out as follows:

Name	Description
DocumentLoaded	Triggers when the document is opened or loaded into the PDF Viewer.
DcoumentUnloaded	Triggers when the document gets closed.
DocumentLoadFailed	Triggers when the document loading gets failed.
AjaxRequestFailed	Triggers when the request gets failed in case of server-side component. Triggers when the communication between service and viewer gets failed in case of client-side component.
ajaxRequestSuccess	Triggers on successful AJAX request.
ajaxRequestInitiate	Triggers before the data is sent to the server.
OnPageClick	Triggers when the click or tap is performed over the page of the PDF document.
PageChanged	Triggers when there is change in current page number.
OnHyperlinkClick	Triggers when the hyperlink (TOC entries and links) in the PDF Document is clicked.
OnHyperlinkMouseOver	Triggers when hyperlink in a PDF document is hovered.
ZoomChanged	Triggers when there is change in the magnification value.
AnnotationAdded	Triggers when an annotation is added over the page of the PDF document.
AnnotationRemoved	Triggers when an annotation is removed from the page of the PDF document.
AnnotationPropertiesChanged	Triggers when the property of the annotation is changed.
AnnotationResized	Triggers when an annotation is resized.
AnnotationSelected	Triggers when an annotation is selected.
AnnotationUnSelect	Triggers when an annotation is unselected over the page of the PDF document.
AnnotationMoved	Triggers when an annotation is moved over the page of the PDF document.
annotationMouseover	Triggers when the mouse is moved over the annotation object.
annotationMouseLeave	Triggers when the user mouse moves away from the annotation object.
Created	Triggers when the PDFViewer component is created.
validateFormFields	Triggers when validation is failed.
addSignature	Triggers when a signature is added to a page of a PDF document.
removeSignature	Triggers when the signature is removed from the page of a PDF document.
moveSignature	Triggers when a signature is moved across the page of a PDF documen.t
signaturePropertiesChange	Triggers when the property of the signature is changed in the page of the PDF document.
resizeSignature	Triggers when the signature is resized and placed on a page of a PDF document.
signatureSelect	Triggers when signature is selected over the page of the PDF document.
pageMouseover	Triggers when moving the mouse over the page.
ImportStarted	Triggers when an imported annotation started to appear in the PDF document.
ExportStarted	Triggers when an exported annotation started in the PDF Viewer.
ImportSucceed	Triggers when the annotations in a PDF document are successfully imported.
ImportFailed	Triggers when the annotations imports in a PDF document fails.
ExportFailed	Triggers when the annotations export in a PDF document fails.
ExtractTextCompleted	Triggers when an text extraction is completed in the PDF Viewer.
OnThumbnailClick	Triggers when the thumbnail in the PDF Viewer’s thumbnail panel is clicked.
BookmarkClick	Triggers when the bookmark is clicked in the PDF Viewer’s bookmark panel.
OnTextSelectionStart	Triggers when the text selection is initiated.
OnTextSelectionEnd	Triggers when the text selection is complete.
DownloadStart	Triggers when the download action is initiated.
ButtonFieldClick	Triggers when the button is clicked.
FormFieldClick	Triggers when the form field is selected.
DownloadEnd	Triggers when the download actions are completed.
PrintStart	Triggers when the print action is initiated.
PrintEnd	Triggers when the print actions are completed.
OnTextSearchStart	Triggers when the text search is initiated.
OnTextSearchComplete	Triggers when the text search is completed.
OnTextSearchHighlight	Triggers when the text search text is highlighted.
commentAdd	Triggers when a comment for the annotation is added to the comment panel.
commentEdit	Triggers when the comment for the annotation in the comment panel is edited.
commentDelete	Triggers when the comment for the annotation in the comment panel is deleted.
commentSelect	Triggers when the comment for the annotation in the comment panel is selected.
commentStatusChanged	Triggers when the annotation’s comment for status is changed in the comment panel.
beforeAddFreeText	Triggers before adding a text in the freeText annotation.
formFieldFocusOut	Triggers when focus out from the form fields.
formFieldAdd	Triggers when a form field is added.
formFieldRemove	Triggers when a form field is removed.
formFieldPropertiesChange	Triggers when a property of form field is changed.
formFieldMouseLeave	Triggers when the mouse cursor leaves the form field.
formFieldMouseover	Triggers when the mouse cursor is over a form field.
formFieldMove	Triggers when a form field is moved.
formFieldResize	Triggers when a form field is resized.
formFieldSelect	Triggers when a form field is selected.
formFieldUnselect	Triggers when a form field is unselected.
formFieldDoubleClick	Triggers when the form field is double-clicked.

Adding PDF Viewer events to Blazor component

The Syncfusion PDF Viewer events has to be wrapped inside the PdfViewerEvents tag.

<SfPdfViewerServer DocumentPath="@DocumentPath" Height="500px" Width="1060px" >
    <PdfViewerEvents DocumentLoaded="@DocumentLoaded"></PdfViewerEvents>
</SfPdfViewerServer>

@code{
    private string DocumentPath { get; set; } = "wwwroot/Data/PDF_Succinctly.pdf";
    private void DocumentLoaded(LoadEventArgs args)
    {
        object PageData = args.PageData;
    }
}

Created event

The Created event is triggered when the PDFViewer component is rendered.

The following code illustrates how to load PDF document on created event.

@using Syncfusion.Blazor.PdfViewerServer
@using Syncfusion.Blazor.PdfViewer

<SfPdfViewerServer DocumentPath="@DocumentPath" Width="560" Height="315">
    <PdfViewerEvents Created="created"></PdfViewerEvents>
</SfPdfViewerServer>

@code 
{
    public string DocumentPath { get; set; }

    //Triggers when the PDFViewer component is created.
    public void created()
    {
        string Link = "http://infolab.stanford.edu/pub/papers/google.pdf";
        System.Net.WebClient webClient = new System.Net.WebClient();
        //Returns the byte array containing the downloaded PDF file.
        byte[] byteArray = webClient.DownloadData(Link);
        //Converting the byte array to Base64 string and sets the document path.
        DocumentPath = "data:application/pdf;base64," + Convert.ToBase64String(byteArray);
    }  
}

NOTE

View sample in GitHub.

NOTE

You can refer to the Blazor PDF Viewer feature tour page for its groundbreaking feature representations. You can also explore the Blazor PDF Viewer example to understand how to explain core features of PDF Viewer.