headerValue function

String? headerValue(
  1. List<HeaderField> headers,
  2. String name
)

All values of header name (case-insensitive) joined with ,, or null when absent.

Implementation

String? headerValue(List<HeaderField> headers, String name) {
  final lower = name.toLowerCase();
  final all = [
    for (final h in headers)
      if (h.name.toLowerCase() == lower) h.value,
  ];
  return all.isEmpty ? null : all.join(',');
}