Calculate age in C# using LINQ

Question

I want to calculate a customer age based on his birth date.

public List<ProductView> GetProductsByStoreAndCategoryID(string storeId, string categoryId)
{
    Authenticate();
    int _storeId = Convert.ToInt32(storeId);
    int _categoryId = Convert.ToInt32(categoryId);

    //selecting customerid
    var _customerId = (from cs in context.customerstores.Where(cs => cs.StoreId == _storeId && cs.IsDefault.Equals(true)) select cs.CustomerId).FirstOrDefault();

    //getting customer date of birth for calculating age and excluding regulated product from the list
    var _DateOfBirth = (from c in context.customers.Where(c => c.CustomerId == _customerId && c.IsBlocked.Equals(false)) select c.DateOfBirth).FirstOrDefault();
}

Here I am getting the date of birth, after that I want to calculate age based on that date of birth. How to do that?

@VijayP.V What would change in the context of question if you removed all the code and leave only `var _DateOfBirth = ......` — Eser, Sep 01 '15 at 09:09
You don't need to use Linq to do this. Just use one of the (many) approaches in the linked thread. Personally I like [this one](http://stackoverflow.com/a/16142434/106159) ;) — Matthew Watson, Sep 01 '15 at 09:10
@Eser i removed unwanted codes. i want write a logic for the calculation. — Vijay P.V, Sep 01 '15 at 09:11

Neel · Accepted Answer · 2015-09-01T09:10:37.930

1

It would be like:

var today = DateTime.Today;

var age = today.Year - _DateOfBirth.Year ; ////If _DateOfBirth is a DateTime  object

if (_DateOfBirth > today.AddYears(-age)) age--;

edited Sep 01 '15 at 09:10

answered Sep 01 '15 at 09:03

Neel

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Thanks man.. its working... This is what i wanted. – Vijay P.V Sep 01 '15 at 09:24

score 0 · Answer 2 · answered Sep 01 '15 at 09:06

Not tested... but should work.

    public static int GetAge(DateTime customerDateOfBirth)
    {
        var now = DateTime.UtcNow;
        var customerAge = now.Year - customerDateOfBirth.Year;
        if (customerDateOfBirth > now.AddYears(-customerAge)) 
            customerAge--;
        return customerAge;
    }

score 0 · Answer 3 · answered Sep 01 '15 at 09:09

var _DateOfBirth = (from c in context.customers.Where(c => c.CustomerId == _customerId && c.IsBlocked.Equals(false)) select c.DateOfBirth).FirstOrDefault();
    Console.WriteLine(_DateOfBirth.Year);
    Console.WriteLine(_DateOfBirth.Day);
    Console.WriteLine(_DateOfBirth.Month);

You can calculated age from above code

Calculate age in C# using LINQ

3 Answers3