C# Accessor and initialization

How can we combine c# accessor declaration and initialization

List<string> listofcountries= new List<string>();
and 
List<string>listofcountries {get;set;}

Is there a way to combine these to statements ?

You can't at the moment. You will be able to in C# 6:

List<string> Countries { get; set; } = new List<string>();

You can even make it a read-only property in C# 6 (hooray!):

List<string> Countries { get; } = new List<string>();

In C# 5, you can either use a non-automatically-implemented property:

// Obviously you can make this read/write if you want
private readonly List<string> countries = new List<string>();
public List<string> Countries { get { return countries; } }

... or initialize it in the constructor:

public List<string> Countries { get; set; }

public Foo()
{
    Countries = new List<string>();
}

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