Could not establish secure channel for SSL/TLS with authority

There is a WCF service in a test machine and it uses https. It has a self signed certificate for the machine dns.

Every time I called the web service it returned an error

Could not establish trust relationship for SSL/TLS secure channel

The binding and endpoint configuration in the client and the server were OK and i could even make the service call successfully through soapUI (a free tool to test web services).

In the end, since the certificate was self signed, and not on my machine, I had to install the certificate in my machine for the call to work.

Install certificate using Windows:

1. - open Internet explorer
2. - open the service site
3. - click on the red "Certificate error" box right next to the address bar
4. - choose view certificates
5. - install certificate
6. - next, select "Place all certificates in the following store"
7. - Select Trusted Root Certification Authorities
8. - accept everything and you're done.

Comparing collections with LINQ

Once in a while i have to call the Distinct LINQ method and, more often than not, i don't want to compare the objects reference. To this effect Microsoft provides the interface IEqualityComparer<T>.
The IEqualityComparer<T> interface implements two methods: bool Equals(T x, T y) and int GetHashCode(T obj). These methods are both used by LINQ to compare objects in collections.
Since i need to compare most of the business objects in my solutions, and don't want to go through the hassle of implementing tens of new classes (one per object) I wanted a generic solution.
Simple enough, I built myself the GenericComparer<T>.

public class GenericComparer<T> : IEqualityComparer<T>
{
public GenericComparer(Func<T, T, bool> equals, Func<T, int> getHashCode)
{
this.equals = equals;
this.getHashCode = getHashCode;
}

readonly Func<T, T, bool> equals;
public bool Equals(T x, T y)
{
return equals(x, y);
}

readonly Func<T, int> getHashCode;
public int GetHashCode(T obj)
{
return getHashCode(obj);
}
}

This worked fine. I could finally just set my comparer directly in my LINQ command. All i had to give was the expression to be used in the Equals and GetHashCode methods.

IEnumerable<mytype> result = collection.Distinct(new GenericComparer<mytype>(((mt1, mt2) => mt1.id == mt2.id), (mt => mt.id.GetHashCode())));

Still, it was more code than I would like to see. Since all I want is to receive all unique elements based on a single expression then that's all i should have to write. A simple tweak to the GenericComparer class and I got a simpler comparer SimpleGenericComparer<T>.

public class SimpleGenericComparer<T> : IEqualityComparer<T>
{
public SimpleGenericComparer(Func<T, int> getHashCode)
{
this.getHashCode = getHashCode;
}

public bool Equals(T x, T y)
{
return getHashCode(x) == getHashCode(y);
}

readonly Func<T, int> getHashCode;
public int GetHashCode(T obj)
{
return getHashCode(obj);
}
}
Having the Equals method simply compare both objects with the GetHashCode expression i could finaly just give the expression with which the comparison will be made.

IEnumerable<mytype> result = collection.Distinct(new SimpleGenericComparer<mytype>(mt => mt.id.GetHashCode());