Imports System
Imports System.Collections.Generic
Imports System.Linq
Module Program
' Data class
Class Item
Public Property A As Integer
Public Property B As Integer
Public Property LabelStr As String
Public Sub New(a As Integer, b As Integer, labelStr As String)
Me.A = a
Me.B = b
Me.LabelStr = labelStr
End Sub
Public Overrides Function ToString() As String
Return $"({A}, {B}, {LabelStr})"
End Function
End Class
' Create dataset
Function MakeData() As List(Of Item)
Return New List(Of Item) From {
New Item(7, 2, "python"),
New Item(8, 3, "c"),
New Item(3, 5, "c++"),
New Item(4, 1, "c#"),
New Item(3, 2, "java"),
New Item(7, 1, "go"),
New Item(1, 2, "rust")
}
End Function
' Sort by column A, then B
Sub SortData(data As List(Of Item))
data.Sort(Function(x, y)
Dim cmp = x.A.CompareTo(y.A)
If cmp <> 0 Then Return cmp
Return x.B.CompareTo(y.B)
End Function)
End Sub
' Print all items
Sub PrintData(data As IEnumerable(Of Item))
For Each item In data
Console.WriteLine(item)
Next
End Sub
' Find first item by label
Function FindByLabel(data As IEnumerable(Of Item), label As String) As Item
Return data.FirstOrDefault(Function(i) i.LabelStr = label)
End Function
' Filter by first column
Function FilterByA(data As IEnumerable(Of Item), value As Integer) As List(Of Item)
Return data.Where(Function(i) i.A = value).ToList()
End Function
Sub Main()
Dim data = MakeData()
SortData(data)
Console.WriteLine("Sorted data:")
PrintData(data)
Console.WriteLine()
Console.WriteLine("Searching for 'java':")
Dim found = FindByLabel(data, "java")
If found IsNot Nothing Then
Console.WriteLine(found)
End If
Console.WriteLine()
Console.WriteLine("Filtering items where A = 7:")
Dim filtered = FilterByA(data, 7)
PrintData(filtered)
End Sub
End Module
' run:
'
' Sorted data:
' (1, 2, rust)
' (3, 2, java)
' (3, 5, c++)
' (4, 1, c#)
' (7, 1, go)
' (7, 2, python)
' (8, 3, c)
'
' Searching for 'java':
' (3, 2, java)
'
' Filtering items where A = 7:
' (7, 1, go)
' (7, 2, python)
'
