TOPIC
about_Format.ps1xml
SHORT DESCRIPTION
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.
LONG DESCRIPTION
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.
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 complex. 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.
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.
System.Globalization.CultureInfoDeserialized.System.Globalization.CultureInfoSystem.Globalization.CultureInfo1616LCIDNameDisplayName
Delete the remainder of the file, except for the opening ,
, and tags and the closing
and tags. You must also delete the
digital signature whenever you change the file.
System.Globalization.CultureInfoDeserialized.System.Globalization.CultureInfoSystem.Globalization.CultureInfo1616LCIDNameDisplayName
Next, create a new column for the Calendar property by adding a new set
of tags. The value of the Calendar property can be
long, so a value of 45 characters is used, as follows:
161645
Now, add a new column item in the table rows, as follows:
LCIDNameCalendarDisplayName
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.
C:\PS> get-culture
LCID Name Calendar DisplayName
---- ---- -------- -----------
1033 en-US System.Globalization.GregorianCalendar English (United States)
The XML in Format.ps1xml Files
The ViewDefinitions section of each Format.ps1xml file contains the
tags that define each view. A typical tag includes the
following tags:
The tag identifies the name of the view.
The tag specifies the object type or types to
which the view applies.
The tag specifies how items in the view will be
combined in groups.
These tags contain the tags that specify how each item will be
displayed.
The tag can contain a tag for each object
type to which the view applies. Or, it can contain a
tag that references a selection set that is defined elsewhere by using
a tag.
The tag contains a tag that specifies the
object property by which items are to be grouped. It also contains either
a