Creating arrays with unknown items and dimensions

.NET
1

Hi,
I’m taking input from a user and need to stick it into an array, the problem is, I don’t know ahead of time how many dimensions the array will have and I also don’t know how many items the user will want to stick in each dimension.

The array will have a maximum number of dimensions of 4, but an unlimited number of items per dimension.

I’m trying to create an unordered html list creator, so I need to know the number of items in each level of the list, and since (As far as I know) you can’t create a multi dimensional array with a dynamic size, I’m feeling a little stuck.

I’ve heard that you can use an object to cater for this kind of thing, but both array and object creation is a little new to me.

Can anyone point me in the right direction please?

2

You are right, objects are the way you want to go. Perhaps you can discuss the requirements in a bit more detail and someone will help you out.

In terms of dynamicly sized arrays, check out the generic collections like the List<T>, it is very, very handy.

3

I agree…

4

I’m familiar with list <of T> and I’m not sure if it’s appropriate for what I’m trying to do.

I want to be able to allow a user to type in the items of a menu in terms of their levels and define their relationships.

So I’ll need to allow the person to first specify how many levels depth the menu goes, then populate 1 item from each level until the last level where they will list all items that belong to the 2nd from final level.

For example:
menu level1 = vehicles
level2 = cars
level3 =toyota (Though with the latest news I wouldn’t by one)
level4= red,blue,green,purple,orange etc

Then repeat the process for vehicles, cars, FORD

When they’ve defined a full path and all children items of the 3rd level they press a button to write what they’ve added to an array. Repeat until menu is complete.

I did consider using standard lists, but I would think it would be much more difficult to create the structure and relationships that I’ve described above.

If someone knows a better way please tell me :slight_smile:

5

You are thinking a bit too concretely here, rather you need a MenuItem class that has a (nullable) Parent property which is a MenuItem. Then you just need a list of the parents and you can drill down to the children recursively.

6

That was way over my head.
As I said, I’m pretty new to object creation, so I need to take baby steps.

I made an attempt with arrays and I got up to the point where I realized that I had wasted my time.

I thought that I could say that each dimension in the array could store it’s own static data, for example, if my array has 4 dimensions, the first dimension contains the highest level menu item and the 4th dimension contains the lowest.

So, objects/classes, how can I get started?

7

Well, wat you want to do is create a MenuItem class as suggested by wwb.

public int ItemID { get; set; }
public int ParentID { get; set; }
public string MenuText { get; set; }

The create a List<MenuItem>.

The top most items parentID can be 0 and as they go into menus, it will change to the id of the item containing them. If that makes sense.

8

As I said I’m new to objects and classes.
Have I implemented the class correctly?


Public Class menuItem
    Public ItemID As Integer
    Public ParentID As Integer
    Public MenuText As String

    Public Property menuItemID() As String
        Get
            ' Gets the property value.
            Return ItemID
        End Get
        Set(ByVal Value As String)
            ' Sets the property value.
            ItemID = Value
        End Set
    End Property

    Public Property ParentMenuItemID() As String
        Get
            ' Gets the property value.
            Return ParentID
        End Get
        Set(ByVal Value As String)
            ' Sets the property value.
            ParentID = Value
        End Set
    End Property

    Public Property MenuItemText() As String
        Get
            ' Gets the property value.
            Return MenuText
        End Get
        Set(ByVal Value As String)
            ' Sets the property value.
            MenuText = Value
        End Set
    End Property
End Class

I’m really not sure where I should go from here.