Question

Let’s say I create a jagged 2d array like so:

public static char[,] phoneLetterMapping = { {'0'}, {'1'}, {'A', 'B', 'C'} };

Now, given the first index of the array, I would like to determine the length of the inner array.

I would like to be able to do something like:

phoneLetterMapping[2].length

I can do that in Java. But the Intellisense menu doesn’t return the normal members of an array when I type in the first bracket of the [][] 2d array.

How do I get the inner array lengths of my 2d array in C#?

Answer 1

The declaration you posted won’t even compile in C#, which is your main issue.

You’ve declared, using char[,] a 2D, non-jagged array, but you’re trying to instantiate a jagged array on the right side of the “=” by using { {'0'}, {'1'}, {'A', 'B', 'C'} }.

Now, if you declare it differently:

public static char[][] phoneLetterMapping = { new[] { '0' }, new[] { '1' }, new[] { 'A', 'B', 'C' } };

Then you can simply call something like:

phoneLetterMapping[0].Length;

The line of code you posted at first, however, won’t compile in C#.