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.

dtb · Accepted Answer · 2012-01-07T19:46:42.357

33

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.

edited Jan 07 '12 at 19:46

answered Mar 06 '10 at 07:41

dtb

3

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. – dtb Mar 06 '10 at 09:28
Is it same to do like everytime checking for the each element of strArray that it is null or not in the for loop ? – Harikrishna Mar 06 '10 at 09:38
To "right fit" the Array to include only those assigned elements, I found [this](http://stackoverflow.com/a/9571134/307454) helpful. – lifebalance Nov 04 '13 at 19:59

score 8 · Answer 2 · answered Mar 06 '10 at 07:40

8

Using LINQ you can try

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

answered Mar 06 '10 at 07:40

Adriaan Stander

1

You beat my 5.37 seconds :) But does the OP want null or non null elements? – slugster Mar 06 '10 at 07:42

score 1 · Answer 3 · answered Mar 06 '10 at 07:41

1

Use LINQ:

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

answered Mar 06 '10 at 07:41

slugster

Mmmmm thanks?!?! The other guys had more concise answers than me. – slugster Mar 06 '10 at 11:18

3 Answers3