I have a listbox with a series of elements and I would like to know the code to find the times that an element repeats, for example:
producto A
producto A
producto A
producto A
producto B
producto B
save in variables that the frequency of A is 4 and the frequency of B is 2.
From the listbox items you can get a collection of strings with the different elements.
From there you can get the different values and the number of occurrences by making a GroupBy with LINQ:
Dim items = ListBox1.Items.Cast(Of String)
Dim totales = items.GroupBy((Function(i) i)) _
.Select(Function(g) new KeyValuePair(Of String, Integer)(g.Key, g.Count()))
For Each item As KeyValuePair(Of String,Integer) In totales
Debug.WriteLine($"{item.Key}: {item.Value}")
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