Available for: UI for ASP.NET MVC | UI for ASP.NET AJAX | UI for Blazor | UI for WPF | UI for WinForms | UI for Xamarin | UI for WinUI | UI for ASP.NET Core | UI for .NET MAUI

New to Telerik Document Processing? Download free 30-day trial


With RadSpreadStreamProcessing you can read spreadsheet documents from the following file formats:

  • XLSX

  • CSV

This functionality is introduced in R3 2022.


The library reads dynamically the document content. To achieve this, the IWorksheetImporter and IWorkbookImporter classes responsible for importing the elements of the document implement IDisposable and keep the corresponding content and settings into the memory until it is disposed.

Read File Data

To read the data from a file, you should parse the desired elements in a sequence keeping the following consecution:

  1. Read the Workbook

  2. Read a Worksheet

  3. Read Columns (optional)

  4. Read Rows

  5. Read Cells

Example 1: Read data from a document

using (System.IO.FileStream fs = new System.IO.FileStream(fileName, FileMode.Open)) 
    using (IWorkbookImporter workBookImporter = SpreadImporter.CreateWorkbookImporter(SpreadDocumentFormat.Xlsx, fs)) 
        foreach (IWorksheetImporter worksheetImporter in workBookImporter.WorksheetImporters) 
            foreach (IRowImporter rowImporter in worksheetImporter.Rows) 
                foreach (ICellImporter cell in rowImporter.Cells) 
                    string value = cell.Value; 
Through the importer objects, you can access the properties of the different elements.

Since R1 2023 SP1 there are separate properties for the formula and the value in the ICellImporter.

See Also

In this article