c# - How to access value out of dictionary whose key is complex type? -

in writing insurance premium calculator basic scheme follows: points assigned predetermined number of attributes, such car-value, num-incidents-in-past, years-experience-driving etc. hene, if car worth $3800, lies within 3001 4000 range warrants 30 points in premium calculation. if num-incidents-in-past 3 or below, warrants 0 points. if 4-5 num-inc points warranted 5. if years-exp between 1-5, warrants 12 points. idea arbitrary value being assigned range of values given number of attributes. premium calculations tallying points warranted each attribute category , multiplying factor i.e 2.5. trying use b. liskov's power of abstractions , srp neatly assign responsiblities design calculator extensible , designed.

based on answer provided drharris here is there c# type representing integer range?

how access value out of following dictionary key generic type range defined drharris?

 //************************abstractions************************    public abstract class absperson    {     public virtual abspolicy apolicy { get; set; }     public virtual string id { get; set; }      public string name { get; set; }     public int age { get; set; }     public virtual string address { get; set; }          }  public abstract class abspolicy {    public virtual string personid { get; set; } //fk   public virtual int propvalue { get; set; }   public virtual int insgroup { get; set; }            }  public abstract class absvaluecategorycalculator: ievaluatepolicy {     //data     public abstract void initrange();     //reference drharris poster generic type signature - public class range<t> t : icomparable<t>     public abstract dictionary<range<int>, int> valuerange {get; set;}     public abstract int tally { get; set; }      //behaviour     public virtual void evaluatepolicydetails(absperson person)     {      } }  public interface ievaluatepolicy {     void evaluatepolicydetails(absperson person); }    //*************************concretions************************** public class carvaluecategorycalculator : absvaluecategorycalculator {     public carvaluecategorycalculator()     {//ctor         initrange();     }      public override void initrange()     {         this.valuerange = new dictionary<range<int>, int>();          this.valuerange.add(new range<int>() { minimum = 1000, maximum = 2000 }, 10);         this.valuerange.add(new range<int>() { minimum = 2001, maximum = 3000 }, 20);          this.valuerange.add(new range<int>() { minimum = 3001, maximum = 4000 }, 30);         this.valuerange.add(new range<int>() { minimum = 4001, maximum = 5000 }, 40);         this.valuerange.add(new range<int>() { minimum = 5001, maximum = 6000 }, 50);         this.valuerange.add(new range<int>() { minimum = 6001, maximum = 7000 }, 60);     }      public override dictionary<range<int>, int> valuerange     {         get; set;     }      public override void evaluatepolicydetails(absperson person)     {            //i trying tally value given wether cars worth lies within range               if (this.valuerange.containskey(new range<int>() { maximum = person.apolicy.propvalue, minimum = person.apolicy.propvalue }))         {             this.tally =         }          console.writeline("good");                 }       public override int tally     {         get;set;     }  }//end class 

(as noted in comments, sam's answer points out dictionary isn't what's wanted here - finds equal keys, whereas op trying find range key contains single value. hash tables aren't geared that.)

you need either override gethashcode , equals in range<t> (which sensible - ideally implementing iequatable<range<t>> @ same time) or create separate type implements iequalitycomparer<range<t>> , pass dictionary constructor.

i on range type, this:

public sealed class range<t> : iequatable<range<t>>     t : icomparable<t>, iequatable<t> {     ...      public override int gethashcode()     {         int hash = 23;         hash = hash * 31 + equalitycomparer.default<t>.gethashcode(minimum);         hash = hash * 31 + equalitycomparer.default<t>.gethashcode(maximum);         return hash;     }       public override bool equals(object other)     {         return equals(other range<t>);     }      public bool equals(range<t> other)     {         if (referenceequals(other, this))         {             return true;         }         if (referenceequals(other, null))         {             return false;         }         return equalitycomparer<t>.default.equals(minimum, other.minimum) &&                equalitycomparer<t>.default.equals(maximum, other.maximum);      } } 

note range<t> type mutable, - that's bad idea dictionary keys. idea make @ least "shallow-immutable" - there's not lot can if