Add-History

Syntax

Add-History
   [[-InputObject] <PSObject[]>]
   [-Passthru]
   [<CommonParameters>]

Description

The Add-History cmdlet adds entries to the end of the session history, that is, the list of commands entered during the current session.

The session history is a list of the commands entered during the session. The session history represents the order of execution, the status, and the start and end times of the command. As you enter each command, PowerShell adds it to the history so that you can reuse it. For more information about the session history, see about_History .

The session history is managed separately from the history maintained by the PSReadLine module. Both histories are available in sessions where PSReadLine is loaded. This cmdlet only works with the session history. For more information see, about_PSReadLine .

You can use the Get-History cmdlet to get the commands and pass them to Add-History , or you can export the commands to a CSV or XML file, then import the commands, and pass the imported file to Add-History . You can use this cmdlet to add specific commands to the history or to create a single history file that includes commands from more than one session.

Examples

Example 1: Add commands to the history of a different session

This example add the commands typed in one PowerShell session to the history of a different PowerShell session.

Get-History | Export-Csv c:\testing\history.csv -IncludeTypeInformation
Import-Csv c:\testing\history.csv | Add-History

The first command gets objects representing the commands in the history and exports them to the History.csv file.

The second command is typed at the command line of a different session. It uses the Import-Csv cmdlet to import the objects in the History.csv file. The pipeline operator ( | ) passes the objects to the Add-History cmdlet, which adds the objects representing the commands in the History.csv file to the current session history.

Example 2: Import and run commands

This example imports commands from the History.xml file, adds them to the current session history, and then runs the commands in the combined history.

Import-Clixml c:\temp\history.xml | Add-History -PassThru | ForEach-Object -Process {Invoke-History}

The first command uses the Import-Clixml cmdlet to import a command history that was exported to the History.xml file. The pipeline operator passes the commands to the Add-History cmdlet, which adds the commands to the current session history. The PassThru parameter passes the objects representing the added commands down the pipeline.

The command then uses the ForEach-Object cmdlet to apply the Invoke-History command to each of the commands in the combined history. The Invoke-History command is formatted as a script block, enclosed in braces ( {} ), as required by the Process parameter of the ForEach-Object cmdlet.

Example 3: Add commands in the history to the end of the history

This example adds the first five commands in the history to the end of the history list.

Get-History -Id 5 -Count 5 | Add-History

The Get-History cmdlet gets the five commands ending in command 5. The pipeline operator passes them to the Add-History cmdlet, which appends them to the current history. The Add-History command does not include any parameters, but PowerShell associates the objects passed through the pipeline with the InputObject parameter of Add-History .

Example 4: Add commands in a .csv file to the current history

This example add the commands in the History.csv file to the current session history.

$a = Import-Csv c:\testing\history.csv
Add-History -InputObject $a -PassThru

The Import-Csv cmdlet imports the commands in the History.csv file and store its contents in the variable $a .

The second command uses the Add-History cmdlet to add the commands from History.csv to the current session history. It uses the InputObject parameter to specify the $a variable and the PassThru parameter to generate an object to display at the command line. Without the PassThru parameter, the Add-History cmdlet does not generate any output.

Example 5: Add commands in an .xml file to the current history

This example adds the commands in the history.xml file to the current session history.

Add-History -InputObject (Import-Clixml c:\temp\history.xml)

The InputObject parameter passes the results of the command in parentheses to the Add-History cmdlet. The command in parentheses, which is executed first, imports the history.xml file into PowerShell. The Add-History cmdlet then adds the commands in the file to the session history.

Parameters

-InputObject

-Passthru

Inputs

HistoryInfo

You can pipe a HistoryInfo object to this cmdlet.

Outputs

None

By default, this cmdlet returns no output.

HistoryInfo

When you use the PassThru parameter, this cmdlet returns a HistoryInfo object.

Notes

The session history is a list of the commands entered during the session together with the ID. The session history represents the order of execution, the status, and the start and end times of the command. As you enter each command, PowerShell adds it to the history so that you can reuse it. For more information about the session history, see about_History .

To specify the commands to add to the history, use the InputObject parameter. The Add-History command accepts only HistoryInfo objects, such as those returned for each command by the Get-History cmdlet. You cannot pass it a path and file name or a list of commands.

You can use the InputObject parameter to pass a file of HistoryInfo objects to Add-History . To do so, export the results of a Get-History command to a file by using the Export-Csv or Export-Clixml cmdlet and then import the file by using the Import-Csv or Import-Clixml cmdlets. You can then pass the file of imported HistoryInfo objects to Add-History through a pipeline or in a variable. For more information, see the examples.

The file of HistoryInfo objects that you pass to the Add-History cmdlet must include the type information, column headings, and all of the properties of the HistoryInfo objects. If you intend to pass the objects back to Add-History , do not use the NoTypeInformation parameter of the Export-Csv cmdlet and do not delete the type information, column headings, or any fields in the file.

To modify the session history, export the session to a CSV or XML file, modify the file, import the file, and use Add-History to append it to the current session history.

Related Links

• Clear-History
• Get-History
• Invoke-History
• about_PSReadLine
• Get-PSReadLineOption
• Set-PSReadLineOption