Scrabble Word Placement C#

Question

I'm currently writing a scrabble-like game in C#. I can get the computer to find the highest point value word that can be made using the current rack, however I have no idea how to check if that word is "Placeable" on the 15*15 Gameboard(2D Array: string[,]).

In it's default state(with no Letters on the board) all elements are set to 0.

Is allowed

---------------
-------H-------
-------E-------
-----FILL------
-------L-------
-------O-------
---------------

How can I check if the word is not For example:

Is Not Allowed

 ---------------
 -H-------------
 -E-------------
FILL------------ <-- F is out of bounds
 -L-------------
 -O-------------
 ---------------

Is Not Allowed

 ---------------
 -H-------------
 -E-W-----------
 -L-O-----------
 -L-R-----------
 FOLL----------- <-- Fill is overlapping with O
 ---D-----------

Answer 1

The paper, "The worlds fastest Scrabble engine" (PDF), is from 1988 and describes an efficient Scrabble engine. It's short and surprisingly readable!