[ebousha]

class First
    {
        string name;
        public string Name
        {
            get { return name; }
            set { name = value; }
        }
        public First(string _name)
        {
            
            name = _name;
        }
        public override int GetHashCode()
        {
            return name.GetHashCode();
        }
    }
    class Second
    {
        int id;
        public int Id
        {
            get { return id; }
            set { id = value; }
        }
        public Second(int _id)
        {
            id = _id;
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            First obj1 = new First("mohamed");
            First obj2 = new First("Ali");
            Second Nobj = new Second(1);
            Hashtable ht = new Hashtable();
            ht[obj1] = Nobj;
            ht[obj2]=Nobj;
            ht.Add(new First("mohamed"), Nobj);           
        }
    }

This post has been edited by tlhIn`toq: 12 October 2012 - 06:41 PM

[Sergio Tapia]

What is your question?
What is supposed to happen?
What actually happens?
Are there errors? If any, paste them here.

[ebousha]

i have two value Similar ,hashtable dont allow enter two Reference similar but i override this option to name , if i enter two name similer i get exception

[Sergio Tapia]

Quote

if i enter two name similer i get exception

Quote

Are there errors? If any, paste them here.

[ebousha]

yes

[Sergio Tapia]

lol

[GunnerInc]

@ebousha, can you be anymore vague? Don't just post code and expect everyone to know what your problem is. Post any errors your compiler is showing you. What are you expecting the outcome to be? What outcome are you getting? The more information you give, the better the help you receive!

[JackOfAllTrades]

Perhaps you are not comfortable in the English language and find it difficult to relay to us what issues you are having. If that's the case you may have better luck in a forum in your native language.

[Momerath]

I believe he's asking why doesn't he get an exception when he adds the third item to his Hashtable since he has an override on the GetHashCode for his class that uses 'name' as the source, and both objects he's adding have the same 'name' value.

[ebousha]

yes Momerath ,this is my problem any body can help me

[barbary]

I'll try to explain.

The HashCode is not the key. The object is the key and the HashCode just helps the hashtable locate the value.

So this is valid

First obj1 = new First("mohamed");
First obj2 = new First("Ali");
Second Nobj = new Second(1);
Hashtable ht = new Hashtable();
ht[obj1] = Nobj;
ht[obj2] = Nobj;
ht.Add(new First("mohamed"), Nobj);
ht.Add(new First("Ali"), Nobj);

This is not

First obj1 = new First("mohamed");
First obj2 = new First("Ali");
Second Nobj = new Second(1);
Hashtable ht = new Hashtable();
ht[obj1] = Nobj;
ht[obj2] = Nobj;
ht.Add(obj1, Nobj);
ht.Add(obj2, Nobj);

However adding this to First will make your orginal example throw an exception

public override bool Equals(object obj)
{
  return this.GetHashCode() == obj.GetHashCode();
}

However this probably just shows that your using hashtable in an inapproriate way, I don't know because you haven't said what your trying to do. Also Dictionary<T,T> is probably better than a hashtable for doing this.

[RexGrammer]

Please be more detailed in your explanation of your problem.

How did you expect the program to behave and how did it actually behave?

This post has been edited by RexGrammer: 30 October 2012 - 06:16 AM