How to handle empty search results in linq

Question

I like to query an list using linq.

It is possible that there are no valid results to the query.

At this moment I get an nullrefenceexception, which I do not want.

What is the best way to solve this ?
https://code.sololearn.com/ctNG0MKEZ0TK/?ref=app

Answer 1

It does not return null. lambda expression returns an Enumerator.
You can use Count there as

if(animals.Where(a => a.StartsWith("a")).Count() != 0 ) {
Console.WriteLine("animal with a");
}
else
{
Console.WriteLine("No animal with a");
}

if Count not equal to 0, then you can use a loop inside if.

Answer 2

Your Lamda expression does not return null.

You can try this way :

foreach(var a in animals)
if(a.StartsWith("a"))
Console.WriteLine("animal with a");
else

Console.WriteLine("No animal with a");

else :

var result = (from a in animals where a.StartsWith("a") select a).ToList();

foreach(var i in result)
Console.WriteLine(i + " animal with a");

Answer 3

I understand I can do it that way. But this is just example code.

I like to use linq and a if statement to determine whether there are any results or no results.