C#. Do if( a == (b or c or d)). Is it possible?

Question

Is there another way to write something like this:

if (a == x || a == y || a == z)

One way that I found is doing it like this:

Answer 1

Fun fact, as of C#9 this is possible

var c ='b';

if (c is 'a' or 'b' or 'c')
  Console.WriteLine("yes");

Which compiles to

if (c == 'a' || c == 'b' || c == 'c')
{
   Console.WriteLine("yes");
}

Or you can get more creative

if (c is (>= 'a' and <= 'z') or (>= 'A' and <= 'Z') or '.' or ',')
   Console.WriteLine("yes");

Which would roughly compile to (according to sharp io)

if (c >= 'a')
{
   if (c <= 'z')
   {
      goto IL_0025;
   }
}
else if (c >= 'A')
{
   if (c <= 'Z')
   {
      goto IL_0025;
   }
}
else if (c == ',' || c == '.')
{
   goto IL_0025;
}
bool flag = false;
goto IL_002b;
IL_0025:
flag = true;
goto IL_002b;
IL_002b:
if (flag)
{
   Console.WriteLine("yes");
}

Or use it in a switch

switch (c)
{
   case 'a' or 'b' or 'c':
      Console.WriteLine("yes");
   break;
}