getFileSize method
Implementation
Future<String> getFileSize(String filepath) async {
var file = File(filepath);
int bytes = await file.length();
if (bytes <= 0) return "0 B";
const suffixes = ["B", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
var i = (log(bytes) / log(1024)).floor();
return ('${(bytes / pow(1024, i)).toStringAsFixed(2)} ${suffixes[i]}')
.toString();
}