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## Advanced Features for Each Language
+### Vector of Unions
+
+Some languages support storing unions directly in a vector.
+
+~~~
+// File found in tests/union_vector/union_vector.fbs
+namespace Example.VectorOfUnions;
+
+// Demonstrates the ability to have vectors of unions, and also to
+// store structs and strings in unions.
+
+table Attacker {
+ sword_attack_damage: int;
+}
+
+struct Rapunzel {
+ hair_length: int;
+}
+
+struct BookReader {
+ books_read: int;
+}
+
+union Character {
+ MuLan: Attacker, // Can have name be different from type.
+ Rapunzel, // Or just both the same, as before.
+ Belle: BookReader,
+ BookFan: BookReader,
+ Other: string,
+ Unused: string
+}
+
+table Movie {
+ main_character: Character;
+ characters: [Character];
+}
+~~~
+
+#### Creating
+
+Analagously to how a union adds two fields to a table a vector of unions creates two different vectors:
+one for the union data and one for the data types.
+
+<div class="language-cpp">
+C++ supports vectors of unions, but it isn't currently documented.
+</div>
+<div class="language-typescript">
+Typescript supports vectors of unions, but it isn't currently documented.
+</div>
+<div class="language-php">
+PHP supports vectors of unions, but it isn't currently documented.
+</div>
+<div class="language-java">
+Java supports vectors of unions, but it isn't currently documented.
+</div>
+<div class="language-csharp">
+~~~{.cs}
+using FlatBuffers;
+using Example.VectorOfUnions;
+
+var fbb = new FlatBufferBuilder(100);
+
+var characterTypes = new[]
+{
+ Character.MuLan,
+ Character.Belle,
+ Character.Other,
+};
+var characterTypesOffset = Movie.CreateCharactersTypeVector(fbb, characterTypes);
+
+var characters = new[]
+{
+ Attacker.CreateAttacker(fbb, 10).Value,
+ BookReader.CreateBookReader(fbb, 20).Value,
+ fbb.CreateSharedString("Chip").Value,
+};
+var charactersOffset = Movie.CreateCharactersVector(fbb, characters);
+
+var movieOffset = Movie.CreateMovie(
+ fbb,
+ Character.Rapunzel,
+ rapunzel,
+ characterTypesOffset,
+ charactersOffset);
+Movie.FinishMovieBuffer(fbb, movieOffset);
+~~~
+</div>
+<div class="language-kotlin">
+Kotlin supports vectors of unions, but it isn't currently documented.
+</div>
+<div class="language-swift">
+Swift supports vectors of unions, but it isn't currently documented.
+</div>
+
+#### Reading
+<div class="language-csharp">
+~~~{.cs}
+var movie = Movie.GetRootAsMovie(fbb.DataBuffer);
+
+for (var i = 0; i <= movie.CharactersLength; i++)
+{
+ if (movie.CharactersType(i) == Character.MuLan)
+ {
+ var mulanSwordDamage = movie.Characters<Attacker>(i).Value.SwordAttackDamage;
+ }
+ else if (movie.CharactersType(i) == Character.Belle)
+ {
+ var belleBooksRead = movie.Characters<BookReader>(i).Value.BooksRead;
+ }
+ else if (movie.CharactersType(i) == Character.Other)
+ {
+ var otherStr = movie.CharactersAsString(i);
+ }
+}
+~~~
+</div>
+
+### Further Reading
+
Each language has a dedicated `Use in XXX` page in the Programmer's Guide
to cover the nuances of FlatBuffers in that language.