ネストされたクラスを使用して戦略パターンを実装しようとしています。
public class Restriction
{
protected SpecificRestriction _specificRestriction;
public void SetGreaterRestriction(decimal value)
{
Greater greaterRestriction = new Greater();
greaterRestriction.GreaterValue = value;
_specificRestriction = greaterRestriction;
}
public void SetLessRestriction(decimal value)
{
Less lessRestriction = new Less();
lessRestriction.LessValue = value;
_specificRestriction = lessRestriction;
}
public void SetRangeRestriction(decimal lessValue, decimal greaterValue)
{
Range r = new Range();
r.GreaterValue= greaterValue;
r.LessValue= lessValue;
_specificRestriction = r;
}
public bool Eval(decimal Value2)
{
return _specificRestriction.Eval(Value2);
}
/* Nested strategies classes */
protected abstract class SpecificRestriction
{
public abstract bool Eval(decimal Value);
}
protected class Less : SpecificRestriction
{
public decimal LessValue { get; set; }
public override bool Eval(decimal lessValue)
{
return lessValue < LessValue ;
}
}
protected class Greater : SpecificRestriction
{
public decimal GreaterValue { get; set; }
public override bool Eval(decimal greaterValue)
{
return greaterValue > GreaterValue;
}
}
protected class Range : SpecificRestriction
{
public decimal LessValue { get; set; }
public decimal GreaterValue { get; set; }
public override bool Eval(decimal mediumValue)
{
return LessValue <= mediumValue && mediumValue <= GreaterValue;
}
}
}
テスト:
Restriction r = new Restriction();
r.SetLessRestriction(12);
r.Eval(13) // Return false <- Works!
r.Eval(11) // Return True <- Works!
r.SetGreaterRestriction(12);
r.Eval(13) // Return True <- Works!
r.Eval(11) // Return False <- Works!
r.SetRangeRestriction(12, 15);
r.Eval(13) // Return false <- It does not works
r.Eval(11) // Return false <- Works!
r.Eval(16) // Return false <- Works!
範囲が機能しないのはなぜですか? Range クラスで何か間違ったことをしていますか?