Does C# (.NET) support partial implementation?

Does C# (.NET) support partial implementation?
No.

the following program will throw an error.

using System;
using System.Collections.Generic;
using System.Text;

namespace OPPTest3
{
interface IA
{
void x();
void y();
}

class IAClass : IA
{
public void x()
{
Console.Out.Write("test x");
}

}
class Program
{
static void Main(string[] args)
{
IAClass m = new IAClass();
m.x();
m.y();
}
}
}