Multiple checks in one cell

Hi everyone,

I have an Excel with a column containing cells with A, B, C or D.

I want to make a function that checks a cell and gives a different answer depending on the letter in the cell (say, for example, A->1, B->2, C->3 and D->4.

How do I write this? I know how to do it where there is only two options, but not with more.