The Format.ps1xml files in Windows PowerShell define the default display of objects in the Windows PowerShell console. You can create your own Format.ps1xml files to change the display of objects or to define default displays for new object types that you create in Windows PowerShell.
The Format.ps1xml files in Windows PowerShell define the default display of objects in Windows PowerShell. You can create your own Format.ps1xml files to change the display of objects or to define default displays for new object types that you create in Windows PowerShell.
When Windows PowerShell displays an object, it uses the data in structured formatting files to determine the default display of the object. The data in the formatting files determines whether the object is rendered in a table or in a list, and it determines which properties are displayed by default.
The formatting affects the display only. It does not affect which object properties are passed down the pipeline or how they are passed. Format.ps1xml files cannot be used to customize the output format for hashtables.
Windows PowerShell includes seven formatting files. These files are located in the installation directory ($pshome). Each file defines the display of a group of Microsoft .NET Framework objects:
Certificate.Format.ps1xml Objects in the Certificate store, such as X.509 certificates and certificate stores.
DotNetTypes.Format.ps1xml Other .NET Framework types, such as CultureInfo, FileVersionInfo, and EventLogEntry objects.
FileSystem.Format.ps1xml File system objects, such as files and directories.
Help.Format.ps1xml Help views, such as detailed and full views, parameters, and examples.
PowerShellCore.format.ps1xml Objects generated by Windows PowerShell core cmdlets, such as Get-Member and Get-History.
PowerShellTrace.format.ps1xml Trace objects, such as those generated by the Trace-Command cmdlet.
Registry.format.ps1xml Registry objects, such as keys and entries.
A formatting file can define four different views of each object: table, list, wide, and custom. For example, when the output of a Get-ChildItem command is piped to a Format-List command, Format-List uses the view in the FileSystem.format.ps1xml file to determine how to display the file and folder objects as a list.
When a formatting file includes more than one view of an object, Windows PowerShell applies the first view that it finds.
In a Format.ps1xml file, a view is defined by a set of XML tags that describe the name of the view, the type of object to which it can be applied, the column headers, and the properties that are displayed in the body of the view. The format in Format.ps1xml files is applied just before the data is presented to the user.
Creating New Format.ps1xml Files
The .ps1xml files that are installed with Windows PowerShell are digitally signed to prevent tampering because the formatting can include script blocks. Therefore, to change the display format of an existing object view, or to add views for new objects, create your own Format.ps1xml files, and then add them to your Windows PowerShell session.
To create a new file, copy an existing Format.ps1xml file. The new file can have any name, but it must have a .ps1xml file name extension. You can place the new file in any directory that is accessible to Windows PowerShell, but it is useful to place the files in the Windows PowerShell installation directory ($pshome) or in a subdirectory of the installation directory.
To change the formatting of a current view, locate the view in the formatting file, and then use the tags to change the view. To create a view for a new object type, create a new view, or use an existing view as a model. (The tags are described in the next section of this topic.) You can then delete all the other views in the file so that the changes are obvious to anyone examining the file.
When you have saved the changes, use the Update-FormatData cmdlet to add the new file to your Windows PowerShell session. If you want your view to take precedence over a view defined in the built-in files, use the PrependData parameter of Update-FormatData. Update-FormatData affects only the current session. To make the change to all future sessions, add the Update-FormatData command to your Windows PowerShell profile.
Example: Adding Calendar Data to Culture Objects
This example shows how to change the formatting of the culture objects (System.Globalization.CultureInfo) generated by the Get-Culture cmdlet. The commands in the example add the calendar property to the default table view display of culture objects.
The first step is to find the Format.ps1xml file that contains the current view of the culture objects. The following Select-String command finds the file:
select-string -path $pshome*format.ps1xml ` -pattern System.Globalization.CultureInfo
This command reveals that the definition is in the DotNetTypes.Format.ps1xml file.
The next command copies the file contents to a new file, MyDotNetTypes.Format.ps1xml.
copy-item DotNetTypes.Format.ps1xml MyDotNetTypes.Format.ps1xml
Next, open the MyDotNetTypes.Format.ps1xml file in any XML or text editor, such as Notepad. Find the System.Globalization.CultureInfo object section. The following XML defines the views of the CultureInfo object. The object has only a TableControl view.
Delete the remainder of the file, except for the opening <?XML>,
Now, add a new column item in the table rows, as follows:
After saving the file and closing it, use an Update-FormatData command, such as the following command, to add the new format file to the current session. The command uses the PrependData parameter to place the new file in a higher precedence order than the original file. (For more information about Update-FormatData, type "get-help update-formatdata".)
update-formatdata -prependpath $pshome\MyDotNetTypes.format.ps1xml
To test the change, type "get-culture", and then review the output, which includes the Calendar property.
LCID Name Calendar DisplayName
1033 en-US System.Globalization.GregorianCalendar English (United States)
The XML in Format.ps1xml FilesThe ViewDefinitions section of each Format.ps1xml file contains the