I'm trying to list all the words with 4 letters. But I'm not sure why it's not working. It will not display it.
This is the code:
IEnumerable<string> query4 = words
.Where(n => n.Length == 4)
.Select(n => n);
DisplayArray(query4);
This is my display method:
private static void DisplayArray<T>(T[] array)
{
foreach (T item in array)
Console.WriteLine(item);
}
Well, according to your current code
private static void DisplayArray<T>(T[] array)
wants array T[] but you provide just IEnumerable<string> and so you should have a compile time error. Change T[] to IEnumrable<T>:
// you have no need in T[], IEnumerable<T> is quite enough
private static void DisplayArray<T>(IEnumerable<T> array) {
foreach (T item in array)
Console.WriteLine(item);
}
Finally (please, notice that Select(n => n) is redundant and can be dropped):
DisplayArray(words.Where(n => n.Length == 4));
T[] (array) implements IEnumerable<T> so if you've implemented a method for IEnumerable<T> it will do for array T[]; the reverse is not trueprivate static void DisplayArray(IEnumerable<string> array)
{
foreach (string item in array)
Console.WriteLine(item);
}
DisplayArray method too hard; what if another Linq returns IEnumerable<int>?
query4isn't an array. Either change your method to takeIEnumerable<T>or useToArray.IEnumerable<T>that only represents a sequence that is not set and you have to materialize it by using aforeachorToListorToArray. Until then it doesn't actually do the filtering or projecting. Also it will do the filtering and projecting each time you materialize it. That's why you'll see a lot of Linq queries ending with aToList.