A Quick Guideline for Microsoft Windows PowerShell - Part 2

Table of Contents

• Introduction
• Background
• VB Script to PowerShell
  • Functions / Methods
• Message to All Silver Members and Above
• Conclusion
• References
• Point of interest
• History

Introduction

The VBA developer as well as VB Script writer are very much familiar with the use of mostly common built-in library or function, for example CInt(), CStr(), Abs()… etc. In this section, we will not discuss how to use this library or function in VB Script. We will discuss how we can convert and use library or function in Microsoft Windows PowerShell.

Background

So, our main objective of this article is to put all mostly used libraries or functions & their use in Microsoft Windows PowerShell under a single article.

It is very important to know that Microsoft Windows PowerShell doesn’t have built-in methods, but we can achieve this by using the .NET Framework library.

Note

This article is a common place for all to participate with proper code snippets and full explanation.

VB Script to PowerShell

In this section, we will discuss how we can convert and use all the libraries or functions which are widely used in VB Script.

Functions / Methods

A list of functions / methods is given below:

1. Abs(): Returns the absolute value of a number.

   Example:

   $result = [math]::abs(-99) 

   Output: 99

2. Asc(): Returns the ANSI character code corresponding to the first letter in a string.

   Example:

   $result = [byte][char] "A"

   Output: 65

3. CBool(): Returns an expression that has been converted to a Variant of subtype Boolean.

   Example:

   $result = 0  // 0 is for false & 1 is for true
   $result = [bool] $result

   Output: False

4. CByte(): Returns an expression that has been converted to a Variant of subtype Byte.

   Example:

   $result = "99.45"
   $result = [byte] $result

   Output: 99

5. CCur(): Returns an expression that has been converted to a Variant of subtype Currency.

   Example:

   $result = "{0:C}" -f 100

   Output: $100.00

6. CDate(): Returns an expression that has been converted to a Variant of subtype Date.

   Example:

   $result = '17/08/2010'
   $result = [datetime]$result  

7. CDbl(): Returns an expression that has been converted to a Variant of subtype Double.

   Example:

   $result = "10.99"
   $result = [double]$result

   Output: 10.99

8. Chr(): Returns the character associated with the specified ANSI character code.

   Example:

   $result = [char]42 

   Output: *

9. CInt(): Returns an expression that has been converted to a Variant of subtype Integer.

   Example:

   $result = "99.96"
   $result = [int] $result  

   Output: 100

10. CLng(): Returns an expression that has been converted to a Variant of subtype Long.

    Example:

    $result = "123456789.45"
    $result = [long] $result

    Output: 123456789

11. Date(): Returns the current system date.

    Example:

    $result = get-date –format d

    Output: 1/2/2002

12. Now(): Returns the current date and time according to the setting of your computer's system date and time.

    Example:

    $result = get-date

    Output: Wednesday, January 02, 2002 1:32:08 AM

13. Cos(): Returns the cosine of an angle.

    Example:

    $result = [math]::cos(45)

    Output: 0.52532198881773

14. CSng(): Returns an expression that has been converted to a Variant of subtype Single.

    Example:

    $result = "99.45"
    $result =  [single] $result   

    Output: 99.45

15. CStr(): Returns an expression that has been converted to a Variant of subtype String.

    Example:

    $result = 99
    $result = [string] $result     

    Output: "99"

16. DateAdd(): Returns a date to which a specified time interval has been added.
    Windows PowerShell you can determine that by using the Get-Date Cmdlet along with the appropriate method. For example, this command calculates the date 37 days from the current date (using the AddDays() method) and stores that value in the variable $result.

    Example:

    $result = get-date
    $result
    $result = (get-date).AddDays(37)
    $result

    Output:

    Wednesday, January 02, 2002 2:31:06 AM
    Friday, February 08, 2002 2:31:06 AM

17. DateDiff(): Returns the number of intervals between two dates.
    Example:

    $result = New-TimeSpan $(Get-Date) $(Get-Date –month 12 -day 31 
    	-year 2006 -hour 23 -minute 30)

    Output:

    Days : 1824
    Hours : 20
    Minutes : 55
    Seconds : 0
    Milliseconds : 0
    Ticks : 1576689000000000
    TotalDays : 1824.87152777778
    TotalHours : 43796.9166666667
    TotalMinutes : 2627815
    TotalSeconds : 157668900
    TotalMilliseconds : 157668900000

18. DatePart(): Returns the specified part of a given date.

    Example:

    $result = (get-date).day
    $result = (get-date).dayofweek
    $result = (get-date).dayofyear
    $result = (get-date).hour
    $result = (get-date).millisecond
    $result = (get-date).minute
    $result = (get-date).month
    $result = (get-date).second
    $result = (get-date).timeofday
    $result = (get-date).year

    Output:

    2
    2
    Wednesday
    2
    2
    921
    41
    1
    50
    
    Days : 0
    Hours : 2
    Minutes : 41
    Seconds : 50
    Milliseconds : 953
    Ticks : 97109531250
    TotalDays : 0.112395290798611
    TotalHours : 2.69748697916667
    TotalMinutes : 161.84921875
    TotalSeconds : 9710.953125
    TotalMilliseconds : 9710953.125

19. DateSerial(): Returns a Variant of subtype Date for a specified year, month, and day.

    Example:

    $result = get-date -y 2010 -mo 12 -day 31

    Output: Friday, December 31, 2010 2:46:44 AM

20. DateValue(): Returns a Variant of subtype Date.

    Example:

    $result = [datetime] "12/1/2010"

    Output: Wednesday, December 01, 2010 12:00:00 AM

21. Day(): Returns a whole number between 1 and 31, inclusive, representing the day of the month.

    Example:

    $result = (get-date).day

    Output: 2

22. Replace(): Returns a string in which a specified substring has been replaced with another substring a specified number of times.

    Example:

    $result = "Hallo"
    $result = $result -replace("a","e")

    Output:

     Hello
    ...... 
    
    
    .... 
    
    
    ... 
    
    
    
    '
    

Message to All Silver Members and Above

This Table of Contents and article are editable by all Silver members and above. What I want you to do is replace the entries in the Table of Contents, add as many as you are aware of on Microsoft Windows PowerShell. This will really help beginners to find all of them under a single article.

References

• Microsoft Development Network

Conclusion

I hope that this might be helpful to you. Enjoy!

History

• 17^th August 2010: Initial post