-
字符串从 a-z 排序。
Map<String, String> map = XXX, List<String> keys = map.keys.toList(); // key排序 keys.sort((a, b) { List<int> al = a.codeUnits; List<int> bl = b.codeUnits; for (int i = 0; i < al.length; i++) { if (bl.length <= i) return 1; if (al[i] > bl[i]) { return 1; } else if (al[i] < bl[i]) return -1; } return 0; });