about_Format.ps1xml

Short description

The Format.ps1xml files in PowerShell define the default display of objects in the 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 PowerShell.

Long description

The Format.ps1xml files in PowerShell define the default display of objects in 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 PowerShell.

When 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 doesn't affect which object properties are passed down the pipeline or how they're passed. Format.ps1xml files can't be used to customize the output format for hash tables.

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:

  1. Certificate.Format.ps1xml

    Objects in the Certificate store, such as X.509 certificates and certificate stores.

  2. DotNetTypes.Format.ps1xml

    Other .NET Framework types, such as CultureInfo, FileVersionInfo, and EventLogEntry objects.

  3. FileSystem.Format.ps1xml

    File system objects, such as files and directories.

  4. Help.Format.ps1xml

    Help views, such as detailed and full views, parameters, and examples.

  5. PowerShellCore.Format.ps1xml

    Objects generated by PowerShell core cmdlets, such as Get-Member and Get-History.

  6. PowerShellTrace.Format.ps1xml

    Trace objects, such as those generated by the Trace-Command cmdlet.

  7. Registry.Format.ps1xml

    Registry objects, such as keys and entries.

A formatting file can define four different views of each object:

  • Table
  • List
  • Wide
  • 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, 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 PowerShell are digitally signed to prevent tampering because the formatting can include script blocks. 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 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 PowerShell, but it's useful to place the files in the 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. You can then delete all the other views in the file so that the changes are obvious to anyone examining the file.

After you save the changes, use the Update-FormatData cmdlet to add the new file to your PowerShell session. If you want your view to take precedence over a view defined in the built-in files, use the PrependPath parameter. Update-FormatData affects only the current session. To make the change to all future sessions, add the Update-FormatData command to your 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 in the current PowerShell session. 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:

$Parms = @{
  Path = "$PSHOME\*Format.ps1xml"
  Pattern = "System.Globalization.CultureInfo"
}

Select-String @Parms
C:\Windows\System32\WindowsPowerShell\v1.0\DotNetTypes.format.ps1xml:113:
     <Name>System.Globalization.CultureInfo</Name>
C:\Windows\System32\WindowsPowerShell\v1.0\DotNetTypes.format.ps1xml:115:
<TypeName>System.Globalization.CultureInfo</TypeName>

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 $PSHome\DotNetTypes.format.ps1xml MyDotNetTypes.Format.ps1xml

Open the MyDotNetTypes.Format.ps1xml file in any XML or text editor, such as Visual Studio Code. Find the System.Globalization.CultureInfo object section. The following XML defines the views of the CultureInfo object. The object has only a TableControl view.

<View>
  <Name>System.Globalization.CultureInfo</Name>
  <ViewSelectedBy>
    <TypeName>Deserialized.System.Globalization.CultureInfo</TypeName>
    <TypeName>System.Globalization.CultureInfo</TypeName>
  </ViewSelectedBy>
  <TableControl>
    <TableHeaders>
      <TableColumnHeader>
        <Width>16</Width>
      </TableColumnHeader>
      <TableColumnHeader>
        <Width>16</Width>
      </TableColumnHeader>
    </TableHeaders>
    <TableRowEntries>
      <TableRowEntry>
        <TableColumnItems>
          <TableColumnItem>
            <PropertyName>LCID</PropertyName>
          </TableColumnItem>
          <TableColumnItem>
            <PropertyName>Name</PropertyName>
          </TableColumnItem>
          <TableColumnItem>
            <PropertyName>DisplayName</PropertyName>
          </TableColumnItem>
        </TableColumnItems>
      </TableRowEntry>
    </TableRowEntries>
  </TableControl>
</View>

Delete the remainder of the file, except for the opening <?xml>, <Configuration>, and <ViewDefinitions> tags and the closing <ViewDefinitions> and <Configuration> tags. If there is a digital signature, delete it from your custom Format.ps1xmlfile.

The MyDotNetTypes.Format.ps1xml file should now look like the following sample:

<?xml version="1.0" encoding="utf-8" ?>
<Configuration>
<ViewDefinitions>
<View>
  <Name>System.Globalization.CultureInfo</Name>
  <ViewSelectedBy>
    <TypeName>Deserialized.System.Globalization.CultureInfo</TypeName>
    <TypeName>System.Globalization.CultureInfo</TypeName>
  </ViewSelectedBy>
  <TableControl>
    <TableHeaders>
      <TableColumnHeader>
        <Width>16</Width>
      </TableColumnHeader>
      <TableColumnHeader>
        <Width>16</Width>
      </TableColumnHeader>
      <TableColumnHeader/>
    </TableHeaders>
    <TableRowEntries>
      <TableRowEntry>
        <TableColumnItems>
          <TableColumnItem>
            <PropertyName>LCID</PropertyName>
          </TableColumnItem>
          <TableColumnItem>
            <PropertyName>Name</PropertyName>
          </TableColumnItem>
          <TableColumnItem>
            <PropertyName>DisplayName</PropertyName>
          </TableColumnItem>
        </TableColumnItems>
      </TableRowEntry>
    </TableRowEntries>
  </TableControl>
</View>
</ViewDefinitions>
</Configuration>

Create a new column for the Calendar property by adding a new set of <TableColumnHeader> tags. The value of the Calendar property can be long, so specify a value of 45 characters as the <Width>.

<TableHeaders>
  <TableColumnHeader>
    <Width>16</Width>
  </TableColumnHeader>
  <TableColumnHeader>
    <Width>16</Width>
  </TableColumnHeader>
  <TableColumnHeader>
    <Width>45</Width>
  </TableColumnHeader>
  <TableColumnHeader/>
</TableHeaders>

Add a new column item for Calendar in the table rows using the <TableColumnItem> and <PropertyName tags:

<TableRowEntries>
  <TableRowEntry>
    <TableColumnItems>
      <TableColumnItem>
        <PropertyName>LCID</PropertyName>
      </TableColumnItem>
      <TableColumnItem>
        <PropertyName>Name</PropertyName>
      </TableColumnItem>
      <TableColumnItem>
        <PropertyName>Calendar</PropertyName>
      </TableColumnItem>
      <TableColumnItem>
        <PropertyName>DisplayName</PropertyName>
      </TableColumnItem>
    </TableColumnItems>
  </TableRowEntry>
</TableRowEntries>

Save and close the file. Use Update-FormatData to add the new format file to the current PowerShell session.

This example uses the PrependPath parameter to place the new file in a higher precedence order than the original file. For more information, see Update-FormatData.

Update-FormatData -PrependPath $PSHOME\MyDotNetTypes.Format.ps1xml

To test the change, type Get-Culture and review the output that includes the Calendar property.

Get-Culture
LCID Name  Calendar                               DisplayName
---- ----  --------                               -----------
1033 en-US System.Globalization.GregorianCalendar English (United States)

The XML in Format.ps1xml files

The full schema definition can be found in Format.xsd in the PowerShell source code repository on GitHub.

The ViewDefinitions section of each Format.ps1xml file contains the <View> tags that define each view. A typical <View> tag includes the following tags:

  • <Name> identifies the name of the view.
  • <ViewSelectedBy> specifies the object type or types to which the view applies.
  • <GroupBy> specifies how items in the view will be combined in groups.
  • <TableControl>, <ListControl>, <WideControl>, and <CustomControl> contain the tags that specify how each item will be displayed.

ViewSelectedBy tag

The <ViewSelectedBy> tag can contain a <TypeName> tag for each object type to which the view applies. Or, it can contain a <SelectionSetName> tag that references a selection set that is defined elsewhere by using a <SelectionSet> tag.

GroupBy tag

The <GroupBy> tag contains a <PropertyName> tag that specifies the object property by which items are to be grouped. It also contains either a <Label> tag that specifies a string to be used as a label for each group or a <CustomControlName> tag that references a custom control defined elsewhere using a <Control> tag. The <Control> tag contains a <Name> tag and a <CustomControl> tag.

TableControlTag

The <TableControl> tag typically contains <TableHeaders> and <TableRowEntries> tags that define the formatting for the table's heads and rows. The <TableHeaders> tag typically contains <TableColumnHeader> tags that contain <Label>, <Width>, and <Alignment> tags. The <TableRowEntries> tag contains <TableRowEntry> tags for each row in the table. The <TableRowEntry> tag contains a <TableColumnItems> tag that contains a <TableColumnItem> tag for each column in the row. Typically, the <TableColumnItem> tag contains either a <PropertyName> tag that identifies the object property to be displayed in the defined location, or a <ScriptBlock> tag that contains script code that calculates a result that is to be displayed in the location.

Note

Script blocks can also be used elsewhere in locations where calculated results can be useful.

The <TableColumnItem> tag can also contain a <FormatString> tag that specifies how the property or the calculated results will be displayed.

ListControl tag

The <ListControl> tag typically contains a <ListEntries> tag. The <ListEntries> tag contains a <ListEntry> tag. The <ListEntry> tag contains a <ListItems> tag. The <ListItems> tag contains <ListItem> tags, which contain <PropertyName> tags. The <PropertyName> tags specify the object property to be displayed at the specified location in the list. If the view selection is defined using a selection set, the <ListControl> and <ListEntry> tags can also contain an <EntrySelectedBy> tag that contains one or more <TypeName> tags. These <TypeName> tags specify the object type that the <ListControl> tag is intended to display.

WideControl tag

The <WideControl> tag typically contains a <WideEntries> tag. The <WideEntries> tag contains one or more <WideEntry> tags. A <WideEntry> tag contains one <WideItem> tag.

A <WideItem> tag must include either a <PropertyName> tag or a <ScriptBlock> tag. A <PropertyName> tag specifies the property to display at the specified location in the view. A <ScriptBlock> tag specifies a script to evaluate and display at the specified location in the view.

A <WideItem> tag can contain a <FormatString> tag that specifies how to display the property.

CustomControl tag

The <CustomControl> tag lets you use a script block to define a format. A <CustomControl> tag typically contains a <CustomEntries> tag that contains multiple <CustomEntry> tags. Each <CustomEntry> tag contains a <CustomItem> tag that can contain a variety of tags that specify contents and formatting of the specified location in the view, including <Text>, <Indentation>, <ExpressionBinding>, and <NewLine> tags.

Default displays in Types.ps1xml

The default displays of some basic object types are defined in the Types.ps1xml file in the $PSHOME directory. The nodes are named PsStandardMembers, and the subnodes use one of the following tags:

  • <DefaultDisplayProperty>
  • <DefaultDisplayPropertySet>
  • <DefaultKeyPropertySet>

For more information, see about_Types.ps1xml.

Tracing Format.ps1xml file use

To detect errors in the loading or application of Format.ps1xml files, use the Trace-Command cmdlet with any of the following format components as the value of the Name parameter:

  • FormatFileLoading
  • FormatViewBinding

For more information, see Trace-Command and Get-TraceSource.

Signing a Format.ps1xml file

To protect the users of your Format.ps1xml file, sign the file using a digital signature. For more information, see about_Signing.

Sample XML for a Format-Table custom view

The following sample creates a Format-Table custom view for the System.IO.DirectoryInfo and System.IO.FileInfo objects created by Get-ChildItem. The custom view is named mygciview and adds the CreationTime column to the table.

The custom view is created from an edited version of the FileSystem.Format.ps1xml file that's stored in $PSHOME on PowerShell 5.1.

After your custom .ps1xml file is saved, use Update-FormatData to include the view in a PowerShell session. For this example, the custom view must use the table format, otherwise, Format-Table fails.

Use Format-Table with the View parameter to specify the custom view's name and format the table's output. For an example of how the command is run, see Format-Table.

$Parms = @{
  Path = "$PSHOME\*Format.ps1xml"
  Pattern = "System.IO.DirectoryInfo"
}
Select-String @Parms
Copy-Item $PSHome\FileSystem.format.ps1xml .\MyFileSystem.Format.ps1xml
Update-FormatData -PrependPath $PSHOME\Format\MyFileSystem.Format.ps1xml

Note

To fit the XML sample within line width limitations, it was necessary to compress some indentation and use line breaks within the code.

<?xml version="1.0" encoding="utf-8" ?>
<Configuration>
    <SelectionSets>
        <SelectionSet>
            <Name>FileSystemTypes</Name>
            <Types>
                <TypeName>System.IO.DirectoryInfo</TypeName>
                <TypeName>System.IO.FileInfo</TypeName>
            </Types>
        </SelectionSet>
    </SelectionSets>
<Controls>
<Control>
<Name>FileSystemTypes-GroupingFormat</Name>
<CustomControl>
 <CustomEntries>
  <CustomEntry>
    <CustomItem>
    <Frame>
    <LeftIndent>4</LeftIndent>
    <CustomItem>
    <Text AssemblyName="System.Management.Automation"
    BaseName="FileSystemProviderStrings"
    ResourceId="DirectoryDisplayGrouping"/>
    <ExpressionBinding>
     <ScriptBlock>
      $_.PSParentPath.Replace("Microsoft.PowerShell.Core\FileSystem::", "")
     </ScriptBlock>
    </ExpressionBinding>
    <NewLine/>
    </CustomItem>
    </Frame>
    </CustomItem>
    </CustomEntry>
 </CustomEntries>
</CustomControl>
</Control>
</Controls>
<ViewDefinitions>
    <View>
    <Name>mygciview</Name>
    <ViewSelectedBy>
        <SelectionSetName>FileSystemTypes</SelectionSetName>
    </ViewSelectedBy>
    <GroupBy>
      <PropertyName>PSParentPath</PropertyName>
      <CustomControlName>FileSystemTypes-GroupingFormat</CustomControlName>
    </GroupBy>
        <TableControl>
            <TableHeaders>
                <TableColumnHeader>
                    <Label>Mode</Label>
                    <Width>7</Width>
                    <Alignment>left</Alignment>
                </TableColumnHeader>
                <TableColumnHeader>
                    <Label>LastWriteTime</Label>
                    <Width>25</Width>
                    <Alignment>right</Alignment>
                </TableColumnHeader>
                <TableColumnHeader>
                    <Label>CreationTime</Label>
                    <Width>25</Width>
                    <Alignment>right</Alignment>
                </TableColumnHeader>
                <TableColumnHeader>
                    <Label>Length</Label>
                    <Width>14</Width>
                    <Alignment>right</Alignment>
                </TableColumnHeader>
                <TableColumnHeader/>
            </TableHeaders>
            <TableRowEntries>
                <TableRowEntry>
                    <Wrap/>
                    <TableColumnItems>
                        <TableColumnItem>
                            <PropertyName>Mode</PropertyName>
                        </TableColumnItem>
                        <TableColumnItem>
                            <ScriptBlock>
                                [String]::Format("{0,10}  {1,8}",
                                    $_.LastWriteTime.ToString("d"),
                                    $_.LastWriteTime.ToString("t"))
                            </ScriptBlock>
                        </TableColumnItem>
                        <TableColumnItem>
                            <ScriptBlock>
                                [String]::Format("{0,10}  {1,8}",
                                    $_.CreationTime.ToString("d"),
                                    $_.LastWriteTime.ToString("t"))
                            </ScriptBlock>
                        </TableColumnItem>
                        <TableColumnItem>
                        <PropertyName>Length</PropertyName>
                        </TableColumnItem>
                        <TableColumnItem>
                            <PropertyName>Name</PropertyName>
                        </TableColumnItem>
                    </TableColumnItems>
                </TableRowEntry>
            </TableRowEntries>
        </TableControl>
    </View>
  </ViewDefinitions>
</Configuration>

See also