Ho una soluzione per interfacciare il concatenamento; l'unico problema con la mia soluzione è che cresce in complessità (scala) con ogni nuovo metodo che si desidera supportare. Ma rappresenta un'API davvero fantastica per l'utente.
Consideriamo che avete 3 metodi, A, B e C, e volete usarli in una catena.
Consideriamo inoltre che non si desidera poter chiamare alcun metodo più di una volta.
ad es.
new Builder().A().B().C(); // OK
new Builder().A().B().A(); // Not OK
Questo può essere realizzato con una certa suggestione serio:
public class Builder : A<Not_A>, B<Not_B>, C<Not_C>, Not_A, Not_B, Not_C, Not_AB, Not_BC, Not_AC, Empty
{
Not_AB A<Not_AB>.A() { return (Not_AB)A(); }
Not_AC A<Not_AC>.A() { return (Not_AC)A(); }
Empty A<Empty>.A() { return (Empty)A(); }
public Not_A A()
{
return (Not_A)this;
}
Not_AB B<Not_AB>.B() { return (Not_AB)B(); }
Not_BC B<Not_BC>.B() { return (Not_BC)B(); }
Empty B<Empty>.B() { return (Empty)B(); }
public Not_B B()
{
return (Not_B)this;
}
Not_AC C<Not_AC>.C() { return (Not_AC)C(); }
Not_BC C<Not_BC>.C() { return (Not_BC)C(); }
Empty C<Empty>.C() { return (Empty)C(); }
public Not_C C()
{
return (Not_C)this;
}
}
public interface Empty { }
public interface A<TRemainder> { TRemainder A(); }
public interface B<TRemainder> { TRemainder B(); }
public interface C<TRemainder> { TRemainder C(); }
public interface Not_A : B<Not_AB>, C<Not_AC> { }
public interface Not_B : A<Not_AB>, C<Not_BC> { }
public interface Not_C : A<Not_AC>, B<Not_BC> { }
public interface Not_AB : C<Empty> { }
public interface Not_BC : A<Empty> { }
public interface Not_AC : B<Empty> { }
E poi, mescolare questo con suggestione di Chris Shain di utilizzare una pila di azioni!
Ho deciso di implementarlo. Nota che non puoi chiamare due volte nessun metodo con questa soluzione di concatenazione. Ho inserito il tuo metodo When
come metodo di estensione.
Ecco il codice chiamante:
int level = 5;
var ninja = NinjaBuilder
.CreateNinja()
.Named("Ninja Boy")
.AtLevel(level)
.WithShurikens(10)
.WithSkill(Skill.HideInShadows)
.When(n => n.Level > 3)
.Build();
ecco la mia Ninja e abilità classi:
public class Ninja
{
public string Name { get; set; }
public int Level { get; set; }
public int Shurikens { get; set; }
public Skill Skill { get; set; }
}
public enum Skill
{
None = 1,
HideInShadows
}
Questa è la classe NinjaBuilder:
public class NinjaBuilder : NinjaBuilder_Sans_Named
{
public static NinjaBuilder CreateNinja() { return new NinjaBuilder(); }
public Stack<Action<Ninja>> _buildActions;
public NinjaBuilder()
{
_buildActions = new Stack<Action<Ninja>>();
}
public override Ninja Build()
{
var ninja = new Ninja();
while (_buildActions.Count > 0)
{
_buildActions.Pop()(ninja);
}
return ninja;
}
public override void AddCondition(Func<Ninja, bool> condition)
{
if (_buildActions.Count == 0)
return;
var top = _buildActions.Pop();
_buildActions.Push(n => { if (condition(n)) { top(n); } });
}
public override Sans_Named_NinjaBuilder Named(string name)
{
_buildActions.Push(n => n.Name = name);
return this;
}
public override Sans_AtLevel_NinjaBuilder AtLevel(int level)
{
_buildActions.Push(n => n.Level = level);
return this;
}
public override Sans_WithShurikens_NinjaBuilder WithShurikens(int shurikenCount)
{
_buildActions.Push(n => n.Shurikens = shurikenCount);
return this;
}
public override Sans_WithSkill_NinjaBuilder WithSkill(Skill skillType)
{
_buildActions.Push(n => n.Skill = skillType);
return this;
}
}
e il resto di questo il codice è solo un overhead per far funzionare le conversioni e le chiamate:
public abstract class NinjaBuilderBase :
EmptyNinjaBuilder,
Named_NinjaBuilder<Sans_Named_NinjaBuilder>,
AtLevel_NinjaBuilder<Sans_AtLevel_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_WithSkill_NinjaBuilder>
{
public abstract void AddCondition(Func<Ninja, bool> condition);
public abstract Ninja Build();
public abstract Sans_WithSkill_NinjaBuilder WithSkill(Skill skillType);
public abstract Sans_WithShurikens_NinjaBuilder WithShurikens(int shurikenCount);
public abstract Sans_AtLevel_NinjaBuilder AtLevel(int level);
public abstract Sans_Named_NinjaBuilder Named(string name);
}
public abstract class NinjaBuilder_Sans_WithSkill : NinjaBuilderBase,
Sans_WithSkill_NinjaBuilder
{
Sans_Named_WithSkill_NinjaBuilder Named_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>.Named(string name) { return (Sans_Named_WithSkill_NinjaBuilder)Named(name); }
Sans_AtLevel_WithSkill_NinjaBuilder AtLevel_NinjaBuilder<Sans_AtLevel_WithSkill_NinjaBuilder>.AtLevel(int level) { return (Sans_AtLevel_WithSkill_NinjaBuilder)AtLevel(level); }
Sans_WithShurikens_WithSkill_NinjaBuilder WithShurikens_NinjaBuilder<Sans_WithShurikens_WithSkill_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_WithShurikens_WithSkill_NinjaBuilder)WithShurikens(shurikenCount); }
}
public abstract class NinjaBuilder_Sans_WithShurikens : NinjaBuilder_Sans_WithSkill,
Sans_WithShurikens_NinjaBuilder,
Sans_WithShurikens_WithSkill_NinjaBuilder
{
Sans_Named_WithShurikens_WithSkill_NinjaBuilder Named_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>.Named(string name) { return (Sans_Named_WithShurikens_WithSkill_NinjaBuilder)Named(name); }
Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder AtLevel_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>.AtLevel(int level) { return (Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder)AtLevel(level); }
Sans_Named_WithSkill_NinjaBuilder Named_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>.Named(string name) { return (Sans_Named_WithSkill_NinjaBuilder)Named(name); }
Sans_AtLevel_WithShurikens_NinjaBuilder AtLevel_NinjaBuilder<Sans_AtLevel_WithShurikens_NinjaBuilder>.AtLevel(int level) { return (Sans_AtLevel_WithShurikens_NinjaBuilder)AtLevel(level); }
Sans_WithShurikens_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_WithShurikens_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_WithShurikens_WithSkill_NinjaBuilder)WithSkill(skillType); }
}
public abstract class NinjaBuilder_Sans_AtLevel : NinjaBuilder_Sans_WithShurikens,
Sans_AtLevel_NinjaBuilder,
Sans_AtLevel_WithShurikens_NinjaBuilder,
Sans_AtLevel_WithSkill_NinjaBuilder,
Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder
{
EmptyNinjaBuilder Named_NinjaBuilder<EmptyNinjaBuilder>.Named(string name) { return Named(name); }
Sans_Named_AtLevel_WithSkill_NinjaBuilder Named_NinjaBuilder<Sans_Named_AtLevel_WithSkill_NinjaBuilder>.Named(string name) { return (Sans_Named_AtLevel_WithSkill_NinjaBuilder)Named(name); }
Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder WithShurikens_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder)WithShurikens(shurikenCount); }
Sans_Named_AtLevel_WithShurikens_NinjaBuilder Named_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>.Named(string name) { return (Sans_Named_AtLevel_WithShurikens_NinjaBuilder)Named(name); }
Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder)WithSkill(skillType); }
Sans_Named_AtLevel_NinjaBuilder Named_NinjaBuilder<Sans_Named_AtLevel_NinjaBuilder>.Named(string name) { return (Sans_Named_AtLevel_NinjaBuilder)Named(name); }
Sans_AtLevel_WithShurikens_NinjaBuilder WithShurikens_NinjaBuilder<Sans_AtLevel_WithShurikens_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_AtLevel_WithShurikens_NinjaBuilder)WithShurikens(shurikenCount); }
Sans_AtLevel_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_AtLevel_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_AtLevel_WithSkill_NinjaBuilder)WithSkill(skillType); }
}
public abstract class NinjaBuilder_Sans_Named : NinjaBuilder_Sans_AtLevel,
Sans_Named_NinjaBuilder,
Sans_Named_AtLevel_NinjaBuilder,
Sans_Named_WithShurikens_NinjaBuilder,
Sans_Named_WithSkill_NinjaBuilder,
Sans_Named_WithShurikens_WithSkill_NinjaBuilder,
Sans_Named_AtLevel_WithSkill_NinjaBuilder,
Sans_Named_AtLevel_WithShurikens_NinjaBuilder
{
EmptyNinjaBuilder WithSkill_NinjaBuilder<EmptyNinjaBuilder>.WithSkill(Skill skillType) { return (EmptyNinjaBuilder)WithSkill(skillType); }
EmptyNinjaBuilder WithShurikens_NinjaBuilder<EmptyNinjaBuilder>.WithShurikens(int shurikenCount) { return (EmptyNinjaBuilder)WithShurikens(shurikenCount); }
EmptyNinjaBuilder AtLevel_NinjaBuilder<EmptyNinjaBuilder>.AtLevel(int level) { return (EmptyNinjaBuilder)AtLevel(level); }
Sans_Named_AtLevel_WithShurikens_NinjaBuilder AtLevel_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>.AtLevel(int level) { return (Sans_Named_AtLevel_WithShurikens_NinjaBuilder)AtLevel(level); }
Sans_Named_WithShurikens_WithSkill_NinjaBuilder WithShurikens_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_Named_WithShurikens_WithSkill_NinjaBuilder)WithShurikens(shurikenCount); }
Sans_Named_WithShurikens_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_Named_WithShurikens_WithSkill_NinjaBuilder)WithSkill(skillType); }
Sans_Named_AtLevel_WithShurikens_NinjaBuilder WithShurikens_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_Named_AtLevel_WithShurikens_NinjaBuilder)WithShurikens(shurikenCount); }
Sans_Named_AtLevel_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_Named_AtLevel_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_Named_AtLevel_WithSkill_NinjaBuilder)WithSkill(skillType); }
Sans_Named_AtLevel_NinjaBuilder AtLevel_NinjaBuilder<Sans_Named_AtLevel_NinjaBuilder>.AtLevel(int level) { return (Sans_Named_AtLevel_NinjaBuilder)AtLevel(level); }
Sans_Named_WithShurikens_NinjaBuilder WithShurikens_NinjaBuilder<Sans_Named_WithShurikens_NinjaBuilder>.WithShurikens(int shurikenCount) { return (Sans_Named_WithShurikens_NinjaBuilder)WithShurikens(shurikenCount); }
Sans_Named_WithSkill_NinjaBuilder WithSkill_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>.WithSkill(Skill skillType) { return (Sans_Named_WithSkill_NinjaBuilder)WithSkill(skillType); }
}
public static class NinjaBuilderExtension
{
public static TBuilderLevel When<TBuilderLevel>(this TBuilderLevel ths, Func<Ninja, bool> condition) where TBuilderLevel : EmptyNinjaBuilder
{
ths.AddCondition(condition);
return ths;
}
}
public interface EmptyNinjaBuilder { void AddCondition(Func<Ninja, bool> condition); Ninja Build(); }
public interface Named_NinjaBuilder<TRemainder> { TRemainder Named(string name); }
public interface AtLevel_NinjaBuilder<TRemainder> { TRemainder AtLevel(int level);}
public interface WithShurikens_NinjaBuilder<TRemainder> { TRemainder WithShurikens(int shurikenCount); }
public interface WithSkill_NinjaBuilder<TRemainder> { TRemainder WithSkill(Skill skillType); }
// level one reductions
public interface Sans_Named_NinjaBuilder :
AtLevel_NinjaBuilder<Sans_Named_AtLevel_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_Named_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_AtLevel_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_AtLevel_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_AtLevel_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_AtLevel_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_WithShurikens_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>,
AtLevel_NinjaBuilder<Sans_AtLevel_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_WithSkill_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_WithSkill_NinjaBuilder>,
AtLevel_NinjaBuilder<Sans_AtLevel_WithSkill_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
// level two reductions
// Named
public interface Sans_Named_AtLevel_NinjaBuilder :
WithShurikens_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_Named_AtLevel_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_Named_WithShurikens_NinjaBuilder :
AtLevel_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_Named_WithSkill_NinjaBuilder :
AtLevel_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
// AtLevel
public interface Sans_AtLevel_WithShurikens_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_AtLevel_WithShurikens_NinjaBuilder>,
WithSkill_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
public interface Sans_AtLevel_WithSkill_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_AtLevel_WithSkill_NinjaBuilder>,
WithShurikens_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
// WithShurikens
public interface Sans_WithShurikens_WithSkill_NinjaBuilder :
Named_NinjaBuilder<Sans_Named_WithShurikens_WithSkill_NinjaBuilder>,
AtLevel_NinjaBuilder<Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder>,
EmptyNinjaBuilder { }
// level three reductions
// Named
public interface Sans_AtLevel_WithShurikens_WithSkill_NinjaBuilder :
Named_NinjaBuilder<EmptyNinjaBuilder>,
EmptyNinjaBuilder { }
// AtLevel
public interface Sans_Named_WithShurikens_WithSkill_NinjaBuilder :
AtLevel_NinjaBuilder<EmptyNinjaBuilder>,
EmptyNinjaBuilder { }
// WithShurikens
public interface Sans_Named_AtLevel_WithSkill_NinjaBuilder :
WithShurikens_NinjaBuilder<EmptyNinjaBuilder>,
EmptyNinjaBuilder { }
// WithSkill
public interface Sans_Named_AtLevel_WithShurikens_NinjaBuilder :
WithSkill_NinjaBuilder<EmptyNinjaBuilder>,
EmptyNinjaBuilder { }
Nota che ora fai esplicito presupposto quando puoi usare "Quando" - solo dopo la tua condizione. Non si applica questo, quindi potrebbe essere soggetto a errori. Anche le tue firme di metodo correnti sono errate - ognuna dovrebbe restituire un 'NinjaBuilder', altrimenti questa non è un'interfaccia fluente – BrokenGlass
Sistemati i sigs del metodo. Avrò una pugnalata nel renderlo esplicito. –
Fammi sapere come va - Ho usato diverse interfacce (e metodi di estensione corrispondenti) per far rispettare l'ordine in passato, sarei felice di vedere qualcosa di più elegante – BrokenGlass