An array of unknown size holding items with variable numbers of values/properties

Question

I'm using a datatable where for each row I want to store some 3 or 4 fields, the fields are of different types, best case number of fields is 3, and I want to note the row_index (of the row in the datatable) as I need it.

So like this I want to store the values (for the fields) for all the rows in the datatable.

Please give me an example, code snippet, or more information about how to structure/access this information for any nth row with the row index (which is also stored)

Answer 1

Arrays must be assigned a length, to allow for any number of elements: use the List class.

For example:

List<int> myInts = new List<int>();
myInts.Add(5);
myInts.Add(10);
myInts.Add(11);
myInts.Count // = 3

To store many values inside of the list, I would suggest creating your own class and storing that. But if you don't want to, you can have a list of lists of objects.

List<List<object>> myList = new List<List<object>();
myList.Add(new List<object>() { 1, "APPLE", "red", "sweet" } );

Answer 2

If you have absolutely no idea what fields can be in each element, your only choice is to create a property bag (map/dictionary) of key value pairs.

You can use an ArrayList or an OrderedDictionary, which allow indexing by ordinal, to hold each property bag element.

Answer 3

You can use XMLDocument to store data. It is flexible enough to store and manipulate data even if you only need to use it in memory.

Answer 4

Hi,

I'm using a datatable where for each row i want to store some 3 or 4 fields...

fields are of different types

(best case:: no:of fields is 3) and i want to note the row_index (of the row in the datatable) as i need it.

so like this i want to store the values(for the fields) for all the rows in the datatable...

Pls give me an e.g (of this scenario)//code snippet// and how to access the fields for any ith row with the row index(which's also stored)