Workbook.LoadDocumentAsync(String, CancellationToken) Method

Loads a document asynchronously from a file.

Namespace: DevExpress.Spreadsheet

Assembly: DevExpress.Docs.v19.2.dll

Declaration

C#

public Task<bool> LoadDocumentAsync(
    string fileName,
    CancellationToken cancellationToken
)

VB.NET

Public Function LoadDocumentAsync(
    fileName As String,
    cancellationToken As CancellationToken
) As Task(Of Boolean)

Parameters

Name	Type	Description
fileName	String	A string that specifies a file to load (including the full path).
cancellationToken	CancellationToken	A CancellationToken object used to trace the requests to cancel an operation.

Returns

Type	Description
Task<Boolean>	A Task<TResult> object that return true if the document was loaded successfully; otherwise, false.

Remarks

The Spreadsheet uses the built-in IFormatDetectorService service implementation to detect the format of the loaded document.

If the format detection fails, the Workbook.InvalidFormatException event fires.

Handle the Workbook.DocumentLoaded event to determine when you can safely modify the loaded document.

The code example below shows how to asynchronously convert an XLSX file to PDF format:

C#

private async void ConvertXlsx2PdfWithCancellation()
{
  using (CancellationTokenSource source = new CancellationTokenSource(10000))
  {
    using (Workbook workbook = new Workbook())
      {
          try
          {
              await workbook.LoadDocumentAsync("Document.xlsx", source.Token);
              await workbook.ExportToPdfAsync("Result.pdf", source.Token);
          }
          catch (OperationCanceledException)
          {
              // Your code to handle cancellation.
          }
      }
  }
}

VB.NET

Private Async Sub ConvertXlsx2PdfWithCancellation()
    Using source As CancellationTokenSource = New CancellationTokenSource(10000)

        Using workbook As Workbook = New Workbook()

            Try
                Await workbook.LoadDocumentAsync("Document.xlsx", source.Token)
                Await workbook.ExportToPdfAsync("Result.pdf", source.Token)
            Catch __unusedOperationCanceledException1__ As OperationCanceledException
            ' Your code to handle cancellation.
            End Try
        End Using
    End Using
End Sub