People who starts learning any programing language have the problem that how they can find out no. of days in a particular month of a year. Sometimes it has been given as assignments to them and sometimes our real world programming creates the situation where we have to do the same, recently I was surfing a forum site and stop by on the same question so thought to write an article about it.
I will write the function in two ways first the traditional approach and second will implement Linq in that
First: The traditional implementation:
Create a Function which will return an integer value of times the particular day will occur in a particular month of the year
/// <summary>
/// Count number of times day will fall in a month of a year
/// </summary>
/// <param name="year">Year in which the month will fall</param>
/// <param name="month">Month for which we need to count the no of days</param>
/// <param name="dayOfWeek">day of week which we wnt to count</param>
/// <returns>Number of times the day will fall in that month</returns>
static int NumberOfParticularDaysInMonth(int year, int month, DayOfWeek dayOfWeek)
{
//create a variable to start from date i.e. 1st of that month in thta year which has passed as arrgument
DateTime startDate = new DateTime(year, month, 1);
//use the function of DateTime class which will return the no of days in thta particular month
int days = DateTime.DaysInMonth(startDate.Year, startDate.Month);
//create and initalize a variable with 0 which will hold no of occurnces in that month
int weekDayCount = 0;
//create a loop to count the number of occurncess of that day
for (int day = 0; day < days; ++day)
{
//add days to the start date and check its day of week is what we are counting for if yes add 1 to our variable else add 0
weekDayCount += startDate.AddDays(day).DayOfWeek == dayOfWeek ? 1 : 0;
}
//return the count variable
return weekDayCount;
}
Now what we need is just to call above function will be like this
int CountDayOfWeekInMonth = NumberOfParticularDaysInMonth(2010, 9, DayOfWeek.Friday);
The Linq Implementation of the same function will go like this
/// <summary>
/// Count number of times day will fall in a month of a year
/// </summary>
/// <param name="year">Year in which the month will fall</param>
/// <param name="month">Month for which we need to count the no of days</param>
/// <param name="dayOfWeek">day of week which we wnt to count</param>
/// <returns>Number of times the day will fall in that month</returns>
static int NumberOfParticularDaysInMonth(int year, int month, DayOfWeek dayOfWeek)
{
//create a variable to start from date i.e. 1st of that month in thta year which has passed as arrgument
DateTime startDate = new DateTime(year, month, 1);
//use the function of DateTime class which will return the no of days in thta particular month
int days = startDate.AddMonths(1).Subtract(startDate).Days;
//use Linq to get the no of occurance of that day
int weekdaycount = Enumerable.Range(1, days)
.Select(item => new DateTime(year, month, item))
.Where(date => date.DayOfWeek == dayOfWeek)
.Count();
//return the count variable
return weekdaycount;
}
Now you can call this above function using the following statement
int CountDayOfWeekInMonth = NumberOfParticularDaysInMonth(2010, 9, DayOfWeek.Friday);
Meetu Choudhary
Microsoft MVP (ASP.Net)
DNS MVM Awardee | Microsoft Certified Professional | Microsoft Certified Technology Specialist |
Co-founder / Webmaster : www.jaipurmentor.com | www.msdotnetmentor.com | www.indiaalt.net | Lead Editor / Webmaster : www.dotnetspider.com | www.silverlightclub.com | interview.msdotnetheaven.com | forum.msdotnetheaven.com | My Blog : http://aspnetbymeetu.blogspot.com | My Profile : www.google.com/profiles/meetuchoudhary
Microsoft MVP (ASP.Net)
DNS MVM Awardee | Microsoft Certified Professional | Microsoft Certified Technology Specialist |
Co-founder / Webmaster : www.jaipurmentor.com | www.msdotnetmentor.com | www.indiaalt.net | Lead Editor / Webmaster : www.dotnetspider.com | www.silverlightclub.com | interview.msdotnetheaven.com | forum.msdotnetheaven.com | My Blog : http://aspnetbymeetu.blogspot.com | My Profile : www.google.com/profiles/meetuchoudhary
