PowerShell ConvertToDateTime

PowerShell Converts a Date to a String with ConvertToDateTime

This page solves the real problem of displaying the boot time.  What it does is convert a hard-to-read number (20121006065349.125599+060) into a meaningful date string (06 October 2012).

Topics for PowerShell ConvertToDateTime

• Locate the Correct WMI Class
• Research Win32_OperatingSystem Properties
• Reveal the LastBootUpTime Property
• The Final Solution to Display LastBootUpTime

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Locate the Correct WMI Class

ConvertToDateTime is a ScriptMethod, we need a vehicle such as the time the computer started in order to apply this PowerShell technique.  I have chosen  LastBootUpTime, this property is likely to belong to a WMI operating system class and this is how I discovered it:

Name
—-
CIM_OperatingSystem
Win32_OperatingSystem
Win32_OperatingSystemAutochkSetting
Win32_SystemOperatingSystem
…

Research Win32_OperatingSystem Properties

The key PowerShell cmdlet for getting to know the properties of other cmdlets is Get-Member, or GM for short.

Digressing!
You can refine the output with the -MemberType parameter, and filter out those properties beginning with _underscore by appending [a-z]*.

Result: LastBootUpTime (For more precise confirmation substitute  -MemberType Property *boot*)

Reveal the LastBootUpTime Property

Problem 1: This simple command does not reveal the time of LastBootUpTime:
Get-WmiObject Win32_OperatingSystem

Problem 2: This technique reveals the Last Boot Time, but I cannot easily understand the format:

Result: 20121006065349.125599+060

Solution: Master the ScriptMethod ConvertToDateTime

Before we apply Get-Member to a new situation, we need to research methods that convert the number into a readable date / time string.  Key point ConvertToDateTime is ScriptMethod (not a plain method).

Note 1: The wildcard * makes sure you see ScriptMethods

The Final Solution to Display LastBootUpTime

Result: 06 October 2012 (I am in the UK)

Note 2: You need to introduce ConvertToDateTime with $Boot.  My point is that you really do require two $Boot. instructions on the last line. 

See how to calculate uptime since the last reboot.

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Get-Date CSV Format

Here is an example which employs another PowerShell cmdlet called ConvertTo-Csv to control the date format.

Note 3: You could change the separator from a comma to a semi-colon by appending this parameter: -Delimiter ";"

See more on ConvertTo-Csv »

Summary of PowerShell ConvertToDateTime

Computing dates are never easy.  This page solves the real problem of displaying the boot time, by converting a hard-to-read number into a meaningful date string.

See more PowerShell examples for syntax advice

• PowerShell Tutorials   • Syntax   • Get-Verb   • PowerShell Nouns   • Get-Credential

• PowerShell -as   • Comparison operators  • Conditional operators   • Real-time Bandwidth Monitor

• Get-Date  • Quotes   • Windows PowerShell   • PowerShell Version Check   • Get-Member

Please email me if you have a better example script. Also please report any factual mistakes, grammatical errors or broken links, I will be happy to correct the fault.