Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 502
  • Last Modified:

Extend vb.Net Class to have New Property

How do you add an new property to an existing .Net Class.   What I want ot do exactlyis add a property to the dateTime class.

The goal would be like this.  
 
Dim intWeek as integer = DateTime.Now.WeekOfMonth

Open in new window


Here is the code I use to get the week of the month.

 Dim DayNo As Integer = 0
                Dim DateNo As Integer = 0
                Dim StartingDay As Integer = 0
                Dim PayPerEndDate As Date = DateTime.Now
                Dim week As Integer = 1
                StartingDay = PayPerEndDate.AddDays(-(PayPerEndDate.Day - 1)).DayOfWeek
                DayNo = PayPerEndDate.DayOfWeek
                DateNo = PayPerEndDate.Day
                week = Fix(DateNo / 7)
                If DateNo Mod 7 > 0 Then
                    week += 1
                End If
                If StartingDay > DayNo Then
                    week += 1
                End If

Open in new window

0
pamsauto
Asked:
pamsauto
  • 2
1 Solution
 
käµfm³d 👽Commented:
How do you add an new property to an existing .Net Class.
You can't...at least not without subclassing it--if it's not sealed. It appears you want to add a member to the Now property, which is a DateTime struct. Structs cannot be inherited. You could add and extension method that would *appear* to be a member method, but in reality it's just a static (Shared in VB) method.
0
 
käµfm³d 👽Commented:
An example of an extension method:

Definition
Public Module MyExtensions

    <System.Runtime.CompilerServices.Extension()>
    Public Function WeekOfMonth(source As DateTime) As Integer
        Dim DayNo As Integer = 0
        Dim DateNo As Integer = 0
        Dim StartingDay As Integer = 0
        Dim PayPerEndDate As Date = source
        Dim week As Integer = 1
        StartingDay = PayPerEndDate.AddDays(-(PayPerEndDate.Day - 1)).DayOfWeek
        DayNo = PayPerEndDate.DayOfWeek
        DateNo = PayPerEndDate.Day
        week = Fix(DateNo / 7)
        If DateNo Mod 7 > 0 Then
            week += 1
        End If
        If StartingDay > DayNo Then
            week += 1
        End If

        Return week
    End Function
End Module

Open in new window


Usage
Dim intWeek as integer = DateTime.Now.WeekOfMonth()

Open in new window

0
 
pamsautoAuthor Commented:
Very nice!
0

Featured Post

Hire Technology Freelancers with Gigs

Work with freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely, and get projects done right.

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now