How to get the total number of days of month from the given date in Salesforce

Some time you may need to calculate the total number of Days in a month from the given input date.  For example suppose if the given date is 05/04/2014(DD/MM/YYYY) means the total number of days in a month will need to return as 31 Days. This can be done by using daysInMonth method.

daysInMonth - Returns the number of days in the month for the specified year and month (1=Jan) the following example finds the number of days in the month of February in the year 1960.

Here is the sample code,

1	Date d = System.today();

2	Integer numberDays = date.daysInMonth(d.Year(), d.Month());

3	System.debug(numberDays);

Reference: Date Methods in Salesforce