DateTime.IsLeapYear() method return a value which indicate whether a specified year is a leap year. this method exists in System namespace. DateTime.IsLeapYear(year) method need to pass a parameter named ‘year’. the ‘year’ parameter value data type is System.Int32 which represent a 4 digit year.
the method return value data type is System.Boolean. so its only return true or false. if the method return true then the specified year is a leap year. otherwise it is not a leap year. if the specified year is less than 1 and greater than 9999 then the method throw an exception named ArgumentOutOfRangeException.
the following asp.net c# example code demonstrate us how can we check whether a specified year is leap year or not programmatically at run time in an asp.net application.
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string checkAnotherYear = DateTime.IsLeapYear(anotherYear).ToString(); |

How to check whether the given year is a leap year C#
ASP.NET
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<%@ Page Language="C#" %> <!DOCTYPE html> <script runat="server"> protected void Button1_Click(object sender, System.EventArgs e) { int year = DateTime.Now.Year; int anotherYear = DateTime.Now.AddYears(3).Year; string checkYear = DateTime.IsLeapYear(year).ToString(); string checkAnotherYear = DateTime.IsLeapYear(anotherYear).ToString(); Label1.Text = "Year " + year; Label1.Text += " Is Leap Year?: " + checkYear; Label1.Text += "<br />Year " + anotherYear; Label1.Text += " Is Leap Year?: " + checkAnotherYear; } </script> <html xmlns="http://www.w3.org/1999/xhtml"> <head id="Head1" runat="server"> <title>code4example.com</title> <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet"> </head> <body> <br /> <form id="form1" runat="server"> <div class="container"> <div class="alert alert-primary" role="alert"> <h2> asp.net date time example:<strong> Leap Year</strong> </h2> </div> <asp:Label ID="Label1" runat="server" CssClass="alert alert-success d-block" > </asp:Label> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" CssClass="btn btn-danger btn-lg" Text="Check Is Leap Year" /> </div> </form> </body> </html> |