Unfortunately, I don't think you can. A work-around though. What about having
a static property in your class that just serves as a wrapper for this
gigantic class name
such as
class SClass
{
string SomeValue
{
get
{
return LognClassName.SomeValue;
}
set
{
LongClassName.SomeValue=value;
}

}
}

Yes.. this is entirely possible using "Using alias directives"

From the documentation:

A using-alias-directive introduces an identifier that serves as an
alias for a namespace or type within the immediately enclosing
compilation unit or namespace body.

using-alias-directive:
using   identifier   =   namespace-or-type-name   ;
Within member declarations in a compilation unit or namespace

For more information take a look at the MSDN documentation.

Dirc

Of course the real question is why you decided to use a long name in
the first place and now want to use an alias?

Personally, I like long names if they are descriptive and helpful. If
you have used this name in the first case, I think it makes code more
readable and understandable if you use this name throughout your code.

Dirc

sorry..Two minutes after I posted this, I realized what Dirk has posted..you
can use something like
using AliasToMyClass = NameSpace1.MyClass;