How to use splatting

Question

I am looking for some help with splatting , I have the below lines to grab a registry key and want it to be passed into a hash table to make it more simpler to view to reduce the length

    if ($Version -ge 16)

    {

       # Grab the value of SAID from the registry based on the instance

       $getTargetResourceReturnValue.SAid = Get-RegistryPropertyValue -Path "HKLM:\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL$($SqlVersion).$($InstanceName)\Setup" -Name "SAID"  
```}

Answer 1

Your hashtable declaration is incorrect. When you are manually creating a hashtable put each value on separate lines.

$getRegistryPropertyParams = @{ 
Path = "HKLM:\SOFTWARE\Microsoft\Microsoft SQLServer\MSSQL$($SqlVersion).$($InstanceName)\Setup"
Name = 'SAID' 
}

If you want to put everything on a single line then PS considers it to be one statement. But you need to generate it as multiple statements so use the semicolon to separate the statements that PS should look at.

$getRegistryPropertyParams = @{ Path = "HKLM:\SOFTWARE\Microsoft\Microsoft SQLServer\MSSQL$($SqlVersion).$($InstanceName)\Setup"; Name = 'SAID' }

Now PS sees the first statement, up to the semicolon as the first line and then everything after that as the second. This is no different than if you manually typed in the first line and pressed ENTER and then entered the second line.

This is how PS works in general so this is not specific to hashtables. Use a semicolon to "insert" a newline in the middle of commands.

Answer 2

"Splatting" is a way to pass parameters to a cmdlet or advanced function. The "splat" is a hashtable (so-named after the "@" character (a.k.a. "splat"))

In the hashtable, each key represents the name of a parameter, and each value is the argument of that parameter.

When you use the hashtable with the function or cmdlet name, be sure to use the "@" decorator and not the usual "$".

https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_splatting?view=powershell-5.1

Here's an example of using your function with splatting:

$props - @{
              Path = "HKLM:\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL$($SqlVersion).$($InstanceName)\Setup"
              Name = "SAID"
          }
$getTargetResourceReturnValue.SAid = Get-RegistryPropertyValue @props