Working with Workbook

13 Jul 20263 minutes to read

After creating or manipulating a workbook with the Syncfusion Flutter XlsIO library, you must save it to the file system and then dispose of the Workbook instance to release the memory consumed by the XlsIO DOM.

Saving an Excel workbook to the file system

The Syncfusion Flutter XlsIO library provides both synchronous and asynchronous APIs to save a workbook in the XLSX format. Use the asynchronous save() method in production code to avoid blocking the UI thread.

Synchronous save

The saveAsStream() method writes the workbook to an in-memory byte buffer synchronously.

  • DART
    • import 'dart:io';
import 'package:syncfusion_flutter_xlsio/xlsio.dart';

Future<void> saveWorkbookSync() async {
  // Create a new workbook.
  final Workbook workbook = Workbook();

  // Access the first worksheet and write a value.
  final Worksheet sheet = workbook.worksheets[0];
  sheet.getRangeByName('A1').setText('Hello, Syncfusion Flutter XlsIO!');

  // Save the workbook as a byte array (XLSX format).
  final List<int> bytes = workbook.saveAsStream();

  // Dispose the workbook to release the XlsIO DOM memory.
  workbook.dispose();

  // Write the bytes to a file. The path is relative to the current working directory.
  await File('Output.xlsx').writeAsBytes(bytes);
}

    Asynchronous save

    The save() method writes the workbook to an in-memory byte buffer asynchronously and is preferred for long-running operations.

  • DART
    • import 'dart:io';
import 'package:syncfusion_flutter_xlsio/xlsio.dart';

Future<void> saveWorkbookAsync() async {
  // Create a new workbook.
  final Workbook workbook = Workbook();

  // Access the first worksheet and write a value.
  final Worksheet sheet = workbook.worksheets[0];
  sheet.getRangeByName('A1').setText('Hello, Syncfusion Flutter XlsIO!');

  // Save the workbook as a byte array (XLSX format).
  final List<int> bytes = await workbook.save();

  // Dispose the workbook to release the XlsIO DOM memory.
  workbook.dispose();

  // Write the bytes to a file. The path is relative to the current working directory.
  await File('Output.xlsx').writeAsBytes(bytes);
}

    Closing a workbook

    Always call dispose() on the Workbook instance after you finish saving it. Failing to dispose of the workbook keeps the XlsIO DOM in memory, which can lead to memory pressure, especially in long-running mobile or web applications. The following code illustrates the recommended try/finally pattern to ensure dispose() is always called, even when an error occurs.

  • DART
    • import 'dart:io';
import 'package:syncfusion_flutter_xlsio/xlsio.dart';

Future<void> saveAndDisposeWorkbook() async {
  // Create a new workbook.
  final Workbook workbook = Workbook();

  try {
    // Save the workbook as a byte array (XLSX format).
    final List<int> bytes = await workbook.save();

    // Write the bytes to a file.
    await File('Output.xlsx').writeAsBytes(bytes);
  } finally {
    // Dispose the workbook to release the XlsIO DOM memory.
    workbook.dispose();
  }
}

    See also