Question

I saw a piece of code which was written like this:

if (from n in numbers select n where n = 5)

However, I tried writing something like this but came across errors (bare in mind the code sample may not be exactly as above as I am typing from memory). How can I write code like the above?

Thanks

Answer 1

In order to use this as a condition, you need to have an expression that returns a boolean. Most likely, this means checking to see if there are any numbers that meet your criteria.

You probably wanted to do:

if ( (from n in numbers where n == 5 select n).Any() )
{
   // Do something
}

Personally, I’d avoid the language integrated syntax, and write this as:

if (numbers.Where(n => n == 5).Any())
{
   // Do something
}

Or even:

if (numbers.Any(n => n == 5))
{
   // Do something
}