Public Class Form1
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        MsgBox(Evaluate("50+50"))
    End Sub
 
    Public Shared Function Evaluate(ByVal expression As String) As Double
        Dim table As New DataTable()
        table.Columns.Add("expression", GetType(String), expression)
        Dim row As DataRow = table.NewRow()
        table.Rows.Add(row)
        Return Double.Parse(DirectCast(row("expression"), String))
    End Function
End Class