toCsv static method
Export data to CSV format
Implementation
static String toCsv(List<Map<String, dynamic>> data, {List<String>? columns}) {
if (data.isEmpty) return '';
final cols = columns ?? data.first.keys.toList();
final buffer = StringBuffer();
// Header row
buffer.writeln(cols.map(_escapeCsvField).join(','));
// Data rows
for (final row in data) {
buffer.writeln(cols.map((col) => _escapeCsvField(row[col]?.toString() ?? '')).join(','));
}
return buffer.toString();
}