Week,month, Year date interval auxiliary class

When we do some business systems, we often use some time-of-access scenarios. For example, you need to count some business data for a certain period of time, such as a week, a month, or a year. At this point we need to get some start and end dates in the current time period. Here is a generic date helper class that allows you to quickly get the starting and ending dates of week, Month, and year based on the date passed in.

public static Class Datehelper

{

public static DateTime Weekfirstday (this datetime dt)

{

DT = datetime.parse (dt. ToString ("Yyyy-mm-dd"));

if (dt. DayOfWeek = = DayOfWeek.Sunday)

{

Return dt. AddDays (-6);

}

Return dt. AddDays (1-(int) dt. DayOfWeek);

}

public static DateTime Weekendday (this datetime dt)

{

DT = datetime.parse (dt. ToString ("Yyyy-mm-dd"));

if (dt. DayOfWeek = = DayOfWeek.Sunday)

{

return DT;

}

Return dt. AddDays (7-(int) dt. DayOfWeek);

}

public static DateTime Monthfirstday (this datetime dt)

{

DT = datetime.parse (dt. ToString ("Yyyy-mm-dd"));

Return dt. AddDays (1-DT. Day);

}

public static DateTime Monthendday (this datetime dt)

{

DT = datetime.parse (dt. ToString ("Yyyy-mm-dd"));

Return dt. AddDays (1-DT. Day). AddMonths (1). AddDays (-1);

}

public static DateTime Yearfirstday (this datetime dt)

{

return new DateTime (dt. Year, 1, 1);

}

public static DateTime Yearendday (this datetime dt)

{

return new DateTime (dt. Year, 12, 31);

}

}

Week,month, Year date interval auxiliary class