The existing documentation has used multiple styles, over time, and the formatting rules have changed multiple times. We want to adopt a consistent style for PowerShell code blocks and output in our documentation. The current Open Publishing System (OPS) we use has a syntax highlighting feature that supports many languages. OPS also adds a Copy button that copies the contents of the code block to the clipboard. This allows you to quickly paste the code into a script for testing the code example. However, not all examples in our documentation are intended to be run. Some code blocks are simple illustrations of a PowerShell concept.
We are defining two scenarios for code blocks:
- Illustrative examples
- Executable examples
Illustrative examples are used to explain a PowerShell concept. They are not meant to be copied to the clipboard for execution. These are most commonly used for simple examples that are easy to type. They are also used for syntax examples where you are illustrating the syntax of a command.
Illustrative examples use a "naked" code fence to mark the beginning and end of the code block. The code block may contain example output from the command being illustrated.
Here is an example of a syntax block:
```
Get-Command [-Verb <String[]>] [-Noun <String[]>] [-Module <String[]>]
[-FullyQualifiedModule <ModuleSpecification[]>] [-TotalCount <Int32>] [-Syntax] [-ShowCommandInfo]
[[-ArgumentList] <Object[]>] [-All] [-ListImported] [-ParameterName <String[]>]
[-ParameterType <PSTypeName[]>] [<CommonParameters>]
```
This example illustrates all of the possible parameters of the Get-Command
cmdlet.
Here is another syntax example describing the for
statement in generalized terms:
```
for (<init>; <condition>; <repeat>)
{<statement list>}
```
Here is an example illustrating PowerShell comparison operators:
```
PS> 2 -eq 2
True
PS> 2 -eq 3
False
PS> 1,2,3 -eq 2
2
PS> "abc" -eq "abc"
True
PS> "abc" -eq "abc", "def"
False
PS> "abc", "def" -eq "abc"
abc
```
Note that this example has the simplified PowerShell prompt and shows the resulting output. In this case, we don't intend the reader to copy this example and try to run the copied code.
More complex examples or examples that would be useful to copy and execute should use
```powershell
… ```
code fence markers. Output emitted by
PowerShell commands should be enclosed in a Output code block to prevent syntax highlighting.
For example:
```powershell
Get-Command -Module Microsoft.PowerShell.Security
```
```Output
CommandType Name Version Source
----------- ---- ------- ------
Cmdlet ConvertFrom-SecureString 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet ConvertTo-SecureString 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-Acl 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-AuthenticodeSignature 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-CmsMessage 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-Credential 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-ExecutionPolicy 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Get-PfxCertificate 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet New-FileCatalog 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Protect-CmsMessage 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Set-Acl 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Set-AuthenticodeSignature 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Set-ExecutionPolicy 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Test-FileCatalog 3.0.0.0 Microsoft.PowerShell.Security
Cmdlet Unprotect-CmsMessage 3.0.0.0 Microsoft.PowerShell.Security
```
The Output code label is not an official "language" supported by the syntax highlighting system. However, this label is useful because OPS adds the "Output" label to the code box on the web page. And this "Output" code box has no syntax highlighting.
OPS also adds a Copy button that copies the contents of the code block to the clipboard. This allows you to quickly paste the code into a script for testing the code example. The Copy button also removes PowerShell prompts from the text before copying it to the clipboard. The Copy button uses the following JavaScript code to remove the prompts.
if (language === 'powershell') {
text = text.replace(/\bPS [a-z]:\\>\s?/gi, '');
}
Note that the regex used only matches simple prompts like "PS C:\>
". Prompts that include
subdirectories or paths from other PSDrive providers will not be removed. See the general
guidelines, in the next section, for the appropriate use of prompts in examples.
-
Code fences
Markdown allows for indentation to signify a code block, but this pattern can be problematic and should be avoided. All code blocks should be contained in a code fence. A code fence is a block of code surrounded by
```
strings. The code fence markers must be on their own line before and after the code sample. The marker at the start of the code block may have an optional language label. See the previous discussion about illustrative and executable examples for the proper use of language labels. -
Line continuation in code samples
Avoid using line continuation characters (`) in PowerShell code examples. These are hard to see and can cause problems if there are extra spaces at the end of the line. Use PowerShell splatting to reduce line length for cmdlets that have a lot of parameters. Take advantage of PowerShell's natural line break opportunities, like after pipe (|) characters and opening braces, parentheses, and brackets.
-
PowerShell prompts in examples
PowerShell prompts should only be used in illustrative examples. Prompts should NOT be used in executable examples. For most of these examples, the prompt string should be "
PS>
". This prompt is independent of OS-specific indicators. Use of the prompt string is discouraged and should be limited to scenarios that are meant to illustrate command line usage. More complex prompt strings are required for examples that illustrate commands that alter the prompt or when the path displayed is significant to the scenario being illustrated. The following example illustrate how the prompt changes when using the Registry provider.``` PS C:\> cd HKCU:\System\ PS HKCU:\System\> dir Hive: HKEY_CURRENT_USER\System Name Property ---- -------- CurrentControlSet GameConfigStore GameDVR_Enabled : 1 GameDVR_FSEBehaviorMode : 2 Win32_AutoGameModeDefaultProfile : {2, 0, 1, 0...} Win32_GameModeRelatedProcesses : {1, 0, 1, 0...} GameDVR_HonorUserFSEBehaviorMode : 0 GameDVR_DXGIHonorFSEWindowsCompatible : 0 ```
See the Updating Reference article.