How many elements of array are not null?

Question

An array is defined of assumed elements like I have array like String[] strArray = new String[50];.

Now from 50 elements only some elements are assigned and remaining are left null then I want the number of assigned elements.

Like here only 30 elements are assigned then I want that figure.

Solution 1

You can use Enumerable.Count:

string[] strArray = new string[50];
...
int result = strArray.Count(s => s != null);

This extension method iterates the array and counts the number of elements the specified predicate applies to.

Solution 2

Using LINQ you can try

int count = strArray.Count(x => x != null);

Solution 3

Use LINQ:

int i = (from s in strArray where !string.IsNullOrEmpty(s) select s).Count();

Comments

[slugster]

You beat my 5.37 seconds :) But does the OP want null or non null elements?

[Feidex]

The code uses LINQ. You need to add using System.Linq; at the top of your source file to make the LINQ extension methods visible.

[Harikrishna]

Is it same to do like everytime checking for the each element of strArray that it is null or not in the for loop ?

[slugster]

Mmmmm thanks?!?! The other guys had more concise answers than me.

[lifebalance]

To "right fit" the Array to include only those assigned elements, I found this helpful.