Question

I am looking for a Java DataOutputStream equivalent for Dart where I can write arbitrary types (int, string, float, byte array etc). There is RandomAccessFile but it does not provide byte array or float-double values. ByteArray seems to have some necessary functions but I am not sure how to write it to a file or an OutputStream.

Answer 1

Here is some simple code showing how to write a ByteArray into an OutputStream:

#import('dart:io');
#import('dart:scalarlist');

main() {
        File file = new File("c:\\temp\\foo.txt");
        OutputStream os = file.openOutputStream();
        os.onNoPendingWrites = () {
                print('Finished writing. Closing.');
                os.flush();
                os.close();
        };
        Uint8List byteList = new Uint8List(64);
        ByteArray byteArray = byteList.asByteArray();
        int offset = 0;
        offset = byteArray.setUint8(offset, 72);
        offset = byteArray.setUint8(offset, 101);
        offset = byteArray.setUint8(offset, 108);
        offset = byteArray.setUint8(offset, 108);
        offset = byteArray.setUint8(offset, 111);
        offset = byteArray.setUint8(offset, 0);
        byteArray.setFloat32(offset, 1.0);
        os.write(byteList);
}