Events in Blazor SfPdfViewer Component

The following events are available in the SfPdfViewer component.

Name Description
AddSignature Triggers when a signature is added to a page in the PDF document.
AnnotationAdded Triggers when an annotation is added to a page in the PDF document.
AnnotationMouseover Triggers when the mouse pointer moves over an annotation object.
AnnotationMoved Triggers when an annotation is moved on a page in the PDF document.
AnnotationPropertiesChanged Triggers when annotation properties are modified on a PDF page.
AnnotationRemoved Triggers when an annotation is removed from a page in the PDF document.
AnnotationResized Triggers when an annotation is resized on a page in the PDF document.
AnnotationSelected Triggers when an annotation is selected on a page in the PDF document.
AnnotationUnselected Triggers when an annotation is unselected on a page in the PDF document.
CommandExecuted Triggers when the designated command is invoked.
Created Triggers when the PDF Viewer component is created.
DocumentEdited Triggers when the PDF document is edited in the SfPdfViewer.
DocumentLoaded Triggers when a document is loaded into the PDF Viewer.
DocumentLoadFailed Triggers when loading a document into the PDF Viewer fails.
DcoumentUnloaded Triggers when the document is closed.
DownloadEnd Triggers when a download action is completed.
DownloadStart Triggers when a download action starts.
ExportFailed Triggers when exporting annotations fails in the SfPdfViewer.
ExportStarted Triggers when exporting annotations starts in the SfPdfViewer.
ExportSucceed Triggers when exporting annotations succeeds in the SfPdfViewer.
ExtractTextCompleted Triggers when text extraction is completed in the SfPdfViewer.
FormFieldAdded Triggered when a form field is added to the PDF document.
FormFieldAdding Triggered before a new form field is added, allowing validation before insertion.
FormFieldClick Triggered when a user clicks on a form field while designer mode is off.
FormFieldDeleted Triggered when a form field is removed from the document.
FormFieldDoubleClick Triggered when a form field is double-clicked.
FormFieldFocusIn Triggered when focus enters a form field.
FormFieldFocusOut Triggered when focus leaves a form field.
FormFieldMouseEnter Triggered when the mouse hovers over a form field.
FormFieldMouseLeave Triggered when the mouse leaves a form field.
FormFieldPropertyChanged Triggered when a form field’s properties are modified.
FormFieldResized Triggered when a form field is resized.
FormFieldSelected Triggered when a form field is selected.
FormFieldsExported Triggered when form fields are successfully exported.
FormFieldsExportFailed Triggered when form fields export operation fails.
FormFieldsExporting Triggered before form fields are exported, allowing customization of the export process.
FormFieldsImported Triggered when form fields are successfully imported.
FormFieldsImportFailed Triggered when form fields import operation fails.
FormFieldsImporting Triggered before form fields are imported, allowing validation or modifications.
FormFieldUnselected Triggered when a form field is unselected.
ImportFailed Triggers when importing annotations fails in the PDF document.
ImportStarted Triggers when importing annotations starts in the PDF document.
ImportSucceed Triggers when importing annotations succeeds in the PDF document.
MoveSignature Triggers when a signature is moved on a page in the PDF document.
OnAnnotationDoubleClick Triggers when an annotation is double-clicked.
OnHyperlinkClick Triggers when a hyperlink in the PDF document is clicked.
OnHyperlinkMouseOver Triggers when a hyperlink in the PDF document is hovered.
OnPageClick Triggers when a mouse click is performed on a page in the PDF document.
OnTextSearchComplete Triggers when a text search is completed.
OnTextSearchHighlight Triggers when searched text is highlighted.
OnTextSearchStart Triggers when a text search starts.
OnTextSelectionEnd Triggers when text selection ends.
OnTextSelectionStart Triggers when text selection starts.
OnThumbnailClick Triggers when a thumbnail is clicked in the thumbnail panel of the SfPdfViewer.
PageChanged Triggers when the current page number changes.
PageMouseover Triggers when the mouse pointer moves over a page.
PrintEnd Triggers when a print action is completed.
PrintStart Triggers when a print action starts.
RemoveSignature Triggers when a signature is removed from a page in the PDF document.
ResizeSignature Triggers when a signature is resized on a page in the PDF document.
SignaturePropertiesChange Triggers when the properties of a signature are changed on a page in the PDF document.
SignatureSelected Triggers when a signature is selected on a page in the PDF document.
SignatureUnselected Triggers when a signature is unselected on a page in the PDF document.
ToolbarClicked Triggers an event when a Custom Toolbar Item is clicked in the Toolbar.
ValidateFormFields Triggered when form fields are validated.
ZoomChanged Triggers when the magnification value changes.

Adding SfPdfViewer events to Blazor component

Wrap the SfPdfViewer events inside the PdfViewerEvents tag.

@using Syncfusion.Blazor.SfPdfViewer

<SfPdfViewer2 DocumentPath="@DocumentPath" Height="100%" Width="100%">
    <PdfViewerEvents DocumentLoaded="DocumentLoaded"></PdfViewerEvents>
</SfPdfViewer2>

@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 Triggers when the PDF Viewer component is rendered.

The following example illustrates how to load a PDF document in the Created event.

@using Syncfusion.Blazor.SfPdfViewer

<SfPdfViewer2  DocumentPath="@DocumentPath" Height="100%" Width="100%">
    <PdfViewerEvents Created="created"></PdfViewerEvents>
</SfPdfViewer2>

@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);
    }  
}

DocumentEdited Event

The DocumentEdited event Triggers when the PDF document is edited.

The following example illustrates how to handle the DocumentEdited event. In this example, EditingAction provides information related to the edit operation.

@using Syncfusion.Blazor.SfPdfViewer 

<SfPdfViewer2 DocumentPath="@DocumentPath" Height="100%" Width="100%"> 
    <PdfViewerEvents DocumentEdited="@DocumentEdited"></PdfViewerEvents>
</SfPdfViewer2>

@code{ 
    private string DocumentPath { get; set; } = "wwwroot/Data/PDF_Succintly.pdf"; 
    public async Task DocumentEdited(DocumentEditedEventArgs args) 
    {
        Console.WriteLine(args.EditingAction);
    }	 
}

View sample in GitHub

See Also