How to calculate age in years from dob in c#

Question

   private void button1_Click(object sender, EventArgs e)
    {
        DateTime dob = new DateTime();
        textBox1.Text = dob.ToString();
        int age;
        age = Convert.ToInt32(textbox2.Text);
        age = DateTime.Now.Year - dob.Year;
        if (DateTime.Now.DayOfYear < dob.DayOfYear)
            age = age - 1;

    }

How to claculate the age from dob.This is my form1.cs.any ideas please

score 10 · Answer 1 · edited Oct 10 '13 at 10:10

10

DateTime today = DateTime.Today;

int age = today.Year - bday.Year;

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

edited Oct 10 '13 at 10:10

Ankur

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answered Oct 10 '13 at 09:44

VasanthRavichandran

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7

2

This is the only correct answer – lethek Jan 12 '17 at 00:42

score 8 · Accepted Answer · answered Feb 08 '13 at 05:20

8

You can calculate it using TimeSpan like:

DateTime dob = .....
DateTime Today = DateTime.Now;
TimeSpan ts = Today - dob;
DateTime Age = DateTime.MinValue + ts;


// note: MinValue is 1/1/1 so we have to subtract...
int Years = Age.Year - 1;
int Months = Age.Month - 1;
int Days = Age.Day - 1;

Source: http://forums.asp.net/t/1289294.aspx/1

answered Feb 08 '13 at 05:20

Habib

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In my testing there are certain dates which this produces incorrect results for :( E.g., try calculating somebody's age on 2017-01-12 when that person was born on 1996-01-13. The above code returns an age of 21 instead of 20, however their 21st birthday should be tomorrow. – lethek Jan 12 '17 at 00:37

gideon · Answer 3 · 2015-04-27T07:08:36.033

0

[Update]: To account for leap years use 365.242 instead of 365. You should be good till the year 2799 I believe.

DateTime has an operator overload, when you use the subtract operator you get a TimeSpan instance.

So you will just do:

DateTime dob = ..
TimeSpan tm = DateTime.Now - dob;
int years = ((tm.Days)/365);

Your code should ideally look like this:

private void button1_Click(object sender, EventArgs e)
{
    DateTime dob = //get this some somewhere..
    textBox1.Text = dob.ToString();
    TimeSpan tm = (DateTime.Now - dob);
    int age = (tm.Days/365) ;
}

The TimeSpan structure represents a time interval, it has properties like Days,Hours,Seconds etc so you could use them if you need.

edited Apr 27 '15 at 07:08

answered Feb 08 '13 at 05:12

gideon

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There is no `Years` property for `TimeSpan` – Habib Feb 08 '13 at 05:16
@Habib Updated answer. I don't think the downvote was called for, I just threw in an answer that was sufficient for the OP while I was fleshing it out. :/ – gideon Feb 08 '13 at 05:18
`I just threw in an answer that was sufficient for the OP while I was fleshing it out` - It shouldn't be this way, your earlier answer was not even compiling that is why the downvote, now I have removed my downvote – Habib Feb 08 '13 at 05:21
I think a wrong answer deserves a down vote, now if he did not remove it after you corrected your error that would be uncalled for. (BTW, there is not 365 days in a year, go ask [Fredric](http://en.wikipedia.org/wiki/The_Pirates_of_Penzance) how old he is) – Scott Chamberlain Feb 08 '13 at 05:22
Alright fair enough :) – gideon Feb 08 '13 at 05:23
in tm.years years is not displaying – Dilipan K Feb 08 '13 at 05:24
1

lol @DilipanK, Hit refresh on this page. – Scott Chamberlain Feb 08 '13 at 05:24
yea I apologize for shooting an answer so quickly :( – gideon Feb 08 '13 at 05:25
How to convert into years – Dilipan K Feb 08 '13 at 05:45
@DilipanK hey I updated my question. Please refresh your page – gideon Feb 08 '13 at 05:48
By hard coding 365 you aren't allowing for leap years. – Spongeboy Jul 16 '14 at 04:58
This algorithm (even when you divide by 365.242 to account for leap years) also produces incorrect results for certain dates. On 2017-01-12, the age of a person who was born on 1976-01-13 is actually 40, but this algorithm calculates it as 41. – lethek Jan 12 '17 at 00:41

How to calculate age in years from dob in c#

3 Answers3