C# comboxbox disable item alternative?

Question

I am trying to write a kiosk program for my print center at a school for students to select size and media type and then have it generate a price. I am currently doing this with radio buttons which works fine but we are adding many more options and a drop down list box would be more appropriate. Also, my code for calculating the price is out of control. I would like to set this up so that calculating the price should be easy. Setup is something like this:

File1 - Paper Size (9 options) - Media Type (18 options) File2, File 3, etc.

I was going to store this in a 3D array filename[]papersize[]media[] for processing the price.

The problem is that not all media types are available in all sizes. I see that you can not disable items in the list. If you pick one size, I can selectively populate the other drop down with or without items, but it changes my index numbers. If I could disable items, I could keep the same index and make an easy loop for processing prices. As it is now I would have to manually specify and loop for each paper size since the media types are different indexes.

I hope this makes sense, I am not really a programmer, I am just trying to make something simple to improve our workflow and accuracy at the print center. I can provide a screen shot of the old program and a mockup of my new program if it would help. Can anyone think of a more elegant solution for this?

Thanks!!

EDIT

Yikes.. Ok, this is ending up to be more difficult than I was expecting: Thanks everyone for your input, it is much appreciated. I did not really expect any responses and there were a lot. Thank You. I attempted the table idea mentioned below but I am not exactly sure how to implement it. I will comment on that post for what I tried. Let me provide more detail in the event that someone else has another idea.

For example of what I am trying to do:

Size = 8.5x11 has media = matte, double sided matte, luster, gloss, acetate, resume Size = 11x17 has media = same minus acetate and resume and so on, up to a 60" roll with backlit media and all sorts of stuff.

Price for 8.5x11 is 1.50 regardless of paper and then each paper has its own price Price for 11x17 is 3.00 and each paper has its own price which is more than their 8.5x11 counterparts

8.5x11 matte = .25
11x17 matte = .50

8.5x11 matte total = 1.75
11x17 matte total = 3.50

I am trying to do this in as little steps as possible. Currently I have radio buttons which take up a bunch a screen real-estate and do things like: When 11x17_1.Checked acetate_1.Disable, etc. Also for calculating price I have hundreds of lines of code doing things like:

 If(8.5x11_1.Checked)
    {
        If(matte_1.Checked) 
            price = 8.5x11matte_1; 
        if(luster_1.Checked) 
            price = 8.5x11luster_1;
        ...etc.
    }  

Rolls require more data (height) to be processed as we charge by linear inch for these. Currently for each file I just have a height box that they are required to fill out. I could just put a height field next to each file for my new version. Then if they select a roll, the height box bust be filled out, which requires more IF's... which I currently have hundreds of. Any thoughts on a more elegant way to do this?

I just don’t have the programming background to simplify this, but I know this can probably be done in 10 lines of code using an array and drop down lists:

It has been a long time since I used arrays but I was thinking of something like:

Selection[file_1][combobox_size.Index][combobox_media.Index]

I think I would have to manually define each array value since the prices are arbitrary?

[0][0][0] = 1.75
[0][0][1] = 1.75
[0][0][2] = 2.00

And so on.

My winform would have let’s say 12 rows for them to enter a file name and then pick the drop down lists. If filename != null then I will process a price for the file and selections.

So if file 1 was 11x17 gloss my array would be something like:

[0][1][3] which I would have pre-defined with a value of $4.00 for example

If it is a roll then I would just multiply by the required height box.

Is this logic sound or grossly inefficient?

EDIT #3

Ok, almost there I think. Sadly, I was unable to figure out the other solutions offered by the community, but I wrote a "get_index" function that looks like this:

public static int get_index(string index)
        {

            if (index == "Matte")
                return (1);
            ....
            if (index == "Luster")
                return (3);
            ....
            else
                return (0);
        }

in my main program I define prices like this:

for (int x = 0; x < filenum; x++)
            {
                pricegrid[x, 0, 0] = 1.75; // 8.5x11 Resume
                pricegrid[x, 0, 1] = 1.75; // 8.5x11 Matte
                pricegrid[x, 0, 2] = 1.75; // 8.5x11 Double Sided Matte
                pricegrid[x, 0, 3] = 2.35; // 8.5x11 Luster
                .....
            }

Then to calculate the price I am doing something like this calling that get_index function:

private void calculate_price()
        {

                getindex[0] = get_index(media1.SelectedItem.ToString());

            ....


        }

Answer 1

There are several ways of doing it. You could create a class FileWithDetail that'd store

[class File / class paper size / class Mediatype ]

Initialize your list at the start of your app

List<FileWithDetail> LstFileWithDetail = new FileWithDetail(){...}

Then with Linq to Object you would easily be able to query the object and bind it to your comboboxes according to your selected value

var LstPaperSize = from p in FileWithDetail
                   where p.FileName == SelectedFileName
                   Select ...   

Answer 2

You should populate your ComboBox dynamically as you do. Instead of using SelectedIndex you can use SelectedValue which does not depend on number of elements.

See for example: Using ValueMember in ComboBox

Answer 3

You shouldn't use one three-dimensional array. You will need 3 tables to that. Store all your types in a database.
3 tables are:
1. paper
2. media
3. papermedia

so. you populate first dropdown with papersizes. then when item is selected in papersizes you run a query to populate dropdown media (you join through intersection table). this way you will only show media that is only available for this papersize. or you can do the other way around. Does this answer your question?