How to generate balance seed using LINQ query

Question

I have some data on the left side of the image below. I want to create a balance seed like the one on the right side using 
Screenshot (22).png

Answer 1

sorry, minor bug (I edited the post and updated)

n.balance = n.balance + p.Sum(r => r.balance);

with

n.balance = n.balance + p.LastOrDefault()?.balance ?? 0;

only need the previous balance, not recalc running total

Answer 2

you need a class for the result data:

class DataDisplay
{
	public string text {get; set;} 
	public Decimal credited {get; set;} 
	public Decimal debited {get; set;} 
	public Decimal balance {get; set;} 
}

then it pretty simple.

var list = getInputData();
var previousBalanceDate = new DateTime(2024, 3,16);

var resultList = list
	.OrderBy(r => r.date)
	.Select(r => new DataDisplay
	{
		text = r.date < previousBalanceDate ? "previous balance" : r.date.ToString("dd-MMM-yy"),
	    credited = r.credited,
	    debited = r.debited,
		balance = r.credited - r.debited
	})
	.Aggregate(new List<DataDisplay>() as IEnumerable<DataDisplay>, (p, n) =>
	{
		n.balance = n.balance + p.LastOrDefault()?.balance ?? 0;
		if (n.text == "previous balance" && p.FirstOrDefault()?.text == "previous balance")
		{
			p.First().balance = n.balance;
			return p;
		}
		return p.Append(n);
	});