Calculate difference in property - arrays

Question

I have converted a list of JSON objects to a generic list.
The Data structure on the items is as following
public class Person
{
private string Name;
private int Age;
private string Weightloss;
}
The Weightloss string is of type "109-102" and I need to calculate how much each person has lost in weight since they signed up. I my examlpe it'd be 7. How to I, using LINQ Method syntax, calculate each weight loss (or gain). I assume I'll need to split up the string but I'm not really sure how

Answer 1

Rather odd question, but if Linq is what you want, here is how one can go about it:
Create a function inside your class to calculate the weight difference:
public class Person
{
//Constructor
public Person(string name, int age, string weightLoss)
{
Name = name;
Age = age;
Weightloss = weightLoss;
}
public string Name;
private int Age;
private string Weightloss;
/// <summary>
/// Calculates the weight difference from the WeightLoss property.
/// </summary>
/// <returns></returns>
public int GetWeightLoss()
{
//Get the values
var parts = Weightloss.Split('-')
.Select(value => Convert.ToInt32(value))
.ToArray();
//Calculate the difference
var difference = parts[0] - parts[1];
return difference;
}
}
Not clean and I personally dislike it but it's homework so...
I added a constructor for initialization and changed the Name field to public so you can output it:
var list = new List<Person>()
{
new Person("Juan", 30, "109-102"),
new Person("Max", 35, "119-103"),
new Person("John", 40, "109-105"),
};
//Figure out the largest loss
var maxLossPerson = list.OrderByDescending(p => p.GetWeightLoss()).First();
Console.WriteLine($"{maxLossPerson.Name} lost the most with {maxLossPerson.GetWeightLoss()} pound(s)");
Output:
Max lost the most with 16 pound(s)

Answer 2

You're either going to use a string split or a regular expression.
Assuming your string is always formatted "Weight1-Weight2", a string split would be fairly simple:
public int[] ParseWeights(string weightString) {
var weights = weightString.Split('-');
var beginningWeight = Convert.ToInt32(weights[0]);
var endingWeight = Convert.ToInt32(weights[1]);
return new int[] {beginningWeight, endingWeight};
}

Answer 3

Add another property to Person:
public class Person
{
private string Name;
private int Age;
private string Weightloss;
public int WeightLost
{
get
{
int[] values = Weightloss.Split('-').Select(i => int.Parse(i)).ToArray();
return values[0] - values[1];
}
}
}

Answer 4

If you look for a even more Linq way, you can use the follow way:
private string Weightloss;
public int WeightLossInt => Weightloss
.Split('-')
.Select((value, index) => index == 0 ? int.Parse(value) : -int.Parse(value))
.Sum();
}