Splatting

How To Use Splatting To Pass Parameters To Commands

Many a times we might have come across the situation where we need to execute the lengthy CmdLets/functions having bunch of parameters and exceeds screen width and wrapped down to the next line or need to scroll towards end of the command or need to ignore the new line using the escape character ( ). Splatting, pass the parameter values as a collection in the form of name and value pair, as a hash table or array of values. It makes the command shorter, easy to read and can be re-used. It’s a hash table/array variable though, to pass the parameter values to the command @ symbol will be used before the variable name instead of $. SYNTAX $paramtable = @{ Name1 = 'Value1' Name2 = 'Value2' Name3 = 'Value3' } C:\> Sample-Command @paramtable or C:\> Sample-Command <optional parameters> @paramtable <optional parameters> To provide the named parameter values hash table can be used and to provide the positional parameters array can be used. When splatting, it is not necessary to use either hash table or an array only to pass the parameters, positional parameters and/or named parameters can also be used along with. EXAMPLE: Splatting with hash table Create a new file using New-Item CmdLet by passing necessary parameters… # Along with the named parameters New-Item -Path C:\Windows\Temp\ -Name Delete.txt -ItemType File -Value "Hello World!" -Force # With hash table $paramtable = @{ Path = 'C:\Windows\Temp\' Name = 'Delete.txt' ItemType = 'File' Value = 'Hello World!' Force = $true } New-Item @paramtable EXAMPLE: Splatting with array Copy a file from one location to other using Copy-Item CmdLet by passing necessary parameters… # Copy a file using named parameters Copy-Item -Path $env:windir\Temp\CSV1.csv -Destination $env:TEMP\CSV1.csv -Force # With array $paramarray = @("$env:windir\Temp\CSV1.csv", "$env:TEMP\CSV1.csv") Copy-Item @paramarray -Force An another example… Function Create-NewItem { [CmdLetBinding(SupportsShouldProcess)] param ( [parameter(mandatory=$true,parametersetname="Path")] [parameter(mandatory=$false,parametersetname="Name")] [string]$Path, [parameter(mandatory=$true,parametersetname="Name")] [string] $Name, [parameter(mandatory=$false,parametersetname="Path")] [parameter(mandatory=$false,parametersetname="Name")] [string]$ItemType, [parameter(mandatory=$false,parametersetname="Path")] [parameter(mandatory=$false,parametersetname="Name")] [object] $Value, [parameter(mandatory=$false,parametersetname="Path")] [parameter(mandatory=$false,parametersetname="Name")] [switch]$Force, [parameter(mandatory=$false,parametersetname="Path")] [parameter(mandatory=$false,parametersetname="Name")] [pscredential] $Credential ) Write-Host "Creating a new $($ItemType.ToLower())" New-Item @PSBoundParameters | Out-Null if ($?) {Write-Host "New $($ItemType.ToLower()) has been created successfully"} } $paramtable = @{ Path = "C:\Temp\" ItemType = "Directory" } Create-NewItem @paramtable <# PS C:\> Create-NewItem @paramtable Creating a new directory New directory has been created successfully #> #Run the script again Create-NewItem @paramtable <# PS C:\> Create-NewItem @paramtable Creating a new directory New-Item : An item with the specified name C:\Temp already exists. At line:25 char:5 + New-Item @PSBoundParameters | Out-Null + ~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : ResourceExists: (C:\Temp:String) [New-Item], IOException + FullyQualifiedErrorId : DirectoryExist,Microsoft.PowerShell.Commands.NewItemCommand #> $paramtable.Force = $true <# PS C:\> $paramtable Name Value ---- ----- Path C:\Temp\ Force True ItemType Directory #> #Run the script again Create-NewItem @paramtable <# PS C:\> Create-NewItem @paramtable Creating a new directory New directory has been created successfully #> $paramtable.Name = 'Test.txt' $paramtable.ItemType = 'File' $paramtable.Remove("Force") <# PS C:\> $paramtable Name Value ---- ----- Path C:\Temp\ Name Test.txt ItemType File #> #Run the script again Create-NewItem @paramtable <# PS C:\> Create-NewItem @paramtable Creating a new file New file has been created successfully #>


21 January 2019