How to create a code from numbers in MS Excel - excel-formula

Question

I have a requirement to create codes from numbers.
Ex . If we define
A as 1
B as 2
...
J as 9
K as 0
And if a cell has value 499 then the equivalent code "DJJ" should be returned.

Answer 1

First, find the character associated with the number '1' in the ASCII table:
=CHAR(1)
This will give you the character associated with ASCII code 1. Now find the code # for A, and then add that to your result:
=CODE("A")
This will give you the ASCII code associated with the letter "A". If you test it out, you will see that there is a specific ordering to the ASCII table. It goes through lowercase letters alphabetically, numbers in order, and capitals alphabetically (with special characters thrown in everywhere in a specific fashion). This ordering allows you to find the letters of the alphabet which come after "A", simply by adding 1, 2, etc - ie:
=CHAR(A1+CODE("A")-1)
This would give you the character associated with a number found in A1, starting at the point where the "A" character rests on the ASCII table.
Finally, assume that A1 holds a 3 digit number. To put the above into a cohesive formula, we just need to apply it 3 times, once for each character in your word. We can do this with the LEFT, MID, and RIGHT functions, as follows:
=CHAR(LEFT(A1)+CODE("A")-1) & CHAR(MID(A1,2,1)+CODE("A")-1) & CHAR(RIGHT(A1)+CODE("A")-1)
This first takes the leftmost character found in A1 (say, the number 5), and adds it to the ASCII code for the letter "A". It then returns the character which is 4 places to the right of "A" in the ASCII table [5 - 1 + CODE("A")]. Then it does this for the 2nd character found in A1 (say, the number 6). Then it does this for the rightmost character in A1 (say, the number 0).
There is no error checking in this method; it assumes A1 always holds a 3 digit number, formatted without decimals.
Note that this method makes 0 = to A. I'll leave it to you to decide if you want to shift all numbers to the right so that 1 = A and 0 = K.