Now, I realize this is pretty advanced, and a lot of you haven't seen some of this more advanced stuff, which is why I'm going through this. Feel free to use this code for your grade manager project. You're going to have to modify some things in here, but I think I've set it up quite nicely so, it will be very helpful. Let's go ahead and step through this, and I can show you line by line what's happening. So, we start from my initial module. This button by the way, just runs the AddEntireColumn subroutine, press F8. So, we call the Combo Box, we Add Item A, B, and we make text A. We go back to the AddEntireColumn Sub. We show UserForm1, which is just this simple box. And I'm going to choose A. I'm going to click Add Item. Then we go into this subroutine. And now if I go through this, we first get the category name from the text here. So, that should be A, I'm going to press F8. I look down here in the Locals window, and CategoryName is A. We then have a message box "please select the directory that contains your files." And it brings up this File Picker and I'm just going to select Add Column Files, click OK. I forgot to put a break point in there, so it actually just went and added A3. I'm not going to worry about deleting those but let's put a couple of break points in here. When you have these dialog boxes and you press Enter a lot of times, it just continues. So, you can't really debug. Let me put a couple break points in there. So now, I'm going to run it. I have to go into the original Sub. I'm going to press F5. I'm going to select A, going to choose that directory Add Column Files, and now, it's stopped at that break point. Now, what am I going to do here? I'm actually going to remove that break point and press F8. So, I'm going to open up the first file, which is File_1. Then, in that case, we would go into the IF statement, but in this case we don't because B1 and C1 are adjacent to each other and those have the same prefix, which is A. So, we bump up to the Next i, now i = 2. We go through here, we count. So, I just added another to that count, we have two. Cell C1 and D1 have the same prefix of A, so we should skip to the Next i. And now, we go to i = 3, and we should see when we do this. First of all, we're going to count the third item here in the category. So, F8, we bump N in category up to three, so there's three A's. But now, when I press F8, cell D1 has a different prefix than cell E1, so in this case, we should go into the IF statement. We're going to determine the FindAddress, which is the address of that next cell, in this case, that should be E1. So, I press F8. You see down here in the Locals window, we picked up E1. Now, we're going to use the Split Function to split E1 using dollar sign as sort of the separator. If I press F8, you see that we've created this FindArray, which actually has a zero element but all we care about is the first element of E and we've got the second element. So the E is what we want in the next line, then we set ColLetter equal to the first element of that FindArray, so that's equal to E. We're now going to select columns E, E colon E which just selects the entire column E. The next line is going to insert a column, to the left is going to shift column E, to the right and add a column and, you see it that's what it did. And finally, we're going to add a new label on there, a new title into the new E1, and that's going to be A4. And we're using the N in category plus one, plus our CategoryName as that title. So, then we're going to go through all the other files. And before we do that though, we have to finish this. If I wanted to, because I've already found a match here, I've already added a column, you could at the very end here, you could say exit for. It doesn't really matter in this case, but maybe if your workbook was really big, you could just do exit for because otherwise, it's just going to keep on searching even though you've already found what you needed to find. I'm pretty confident this is working. I'm going to remove this break point and this break point and I'm going to go down here to debug, run to cursor. It's going to go through all the other four files and do the same thing. And finally, if I run this last one A column for A4 has been added to the files. And finally, we're going to unload UserForm1, and then, we're done with this Sub. It returns to our original Sub and we press F8 once again and we're done. And if you open up those files then, you will notice that all of them have A4, which is the fourth category of A that we've added to the files. And you could do this with your homework assignments, with exams, quizzes, labs and so on. So, this should give you a really good idea of how to Add Columns, iterate through all the workbooks Add Columns. And this will help you a lot with your grade manager project. Good luck and thanks for watching.
