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Add-Content

  • Reference
Module:
Microsoft.PowerShell.Management

Adds content to the specified items, such as adding words to a file.

Syntax

Add-Content
   [-Path] <string[]>
   [-Value] <Object[]>
   [-PassThru]
   [-Filter <string>]
   [-Include <string[]>]
   [-Exclude <string[]>]
   [-Force]
   [-Credential <pscredential>]
   [-WhatIf]
   [-Confirm]
   [-NoNewline]
   [-Encoding <Encoding>]
   [-AsByteStream]
   [-Stream <string>]
   [<CommonParameters>]
Add-Content
   [-Value] <Object[]>
   -LiteralPath <string[]>
   [-PassThru]
   [-Filter <string>]
   [-Include <string[]>]
   [-Exclude <string[]>]
   [-Force]
   [-Credential <pscredential>]
   [-WhatIf]
   [-Confirm]
   [-NoNewline]
   [-Encoding <Encoding>]
   [-AsByteStream]
   [-Stream <string>]
   [<CommonParameters>]

Description

The Add-Content cmdlet appends content to a specified item or file. You can specify the content by typing the content in the command or by specifying an object that contains the content.

If you need to create files or directories for the following examples, see New-Item.

Examples

Example 1: Add a string to all text files with an exception

This example appends a value to text files in the current directory but excludes files based on their file name.

Add-Content -Path .\*.txt -Exclude help* -Value 'End of file'

The Path parameter specifies all .txt files in the current directory, but the Exclude parameter ignores file names that match the specified pattern. The Value parameter specifies the text string that is written to the files.

Use Get-Content to display the contents of these files.

Example 2: Add a date to the end of the specified files

This example appends the date to files in the current directory and displays the date in the PowerShell console.

Add-Content -Path .\DateTimeFile1.log, .\DateTimeFile2.log -Value (Get-Date) -PassThru
Get-Content -Path .\DateTimeFile1.log

Tuesday, May 14, 2019 8:24:27 AM
Tuesday, May 14, 2019 8:24:27 AM
5/14/2019 8:24:27 AM

The Add-Content cmdlet creates two new files in the current directory. The Value parameter contains the output of the Get-Date cmdlet. The PassThru parameter outputs the added contents to the pipeline. Because there is no other cmdlet to receive the output, it is displayed in the PowerShell console. The Get-Content cmdlet displays the updated file, DateTimeFile1.log.

Example 3: Add the contents of a specified file to another file

This example gets the content from a file and stores the content in a variable. The variable is used to append the content into another file.

$From = Get-Content -Path .\CopyFromFile.txt
Add-Content -Path .\CopyToFile.txt -Value $From
Get-Content -Path .\CopyToFile.txt
  • The Get-Content cmdlet gets the contents of CopyFromFile.txt and stores the contents in the $From variable.
  • The Add-Content cmdlet updates the CopyToFile.txt file using the contents of the $From variable.
  • The Get-Content cmdlet displays CopyToFile.txt.

Example 4: Add the contents of a specified file to another file using the pipeline

This example gets the content from a file and pipes it to the Add-Content cmdlet.

Get-Content -Path .\CopyFromFile.txt | Add-Content -Path .\CopyToFile.txt
Get-Content -Path .\CopyToFile.txt

The Get-Content cmdlet gets the contents of CopyFromFile.txt. The results are piped to the Add-Content cmdlet, which updates the CopyToFile.txt. The last Get-Content cmdlet displays CopyToFile.txt.

Example 5: Create a new file and copy content

This example creates a new file and copies an existing file's content into the new file.

Add-Content -Path .\NewFile.txt -Value (Get-Content -Path .\CopyFromFile.txt)
Get-Content -Path .\NewFile.txt
  • The Add-Content cmdlet uses the Path and Value parameters to create a new file in the current directory.
  • The Get-Content cmdlet gets the contents of an existing file, CopyFromFile.txt and passes it to the Value parameter. The parentheses around the Get-Content cmdlet ensure that the command finishes before the Add-Content command begins.
  • The Get-Content cmdlet displays the contents of the new file, NewFile.txt.

Example 6: Add content to a read-only file

This command adds a value to the file even if the IsReadOnly file attribute is set to True. The steps to create a read-only file are included in the example.

New-Item -Path .\IsReadOnlyTextFile.txt -ItemType File
Set-ItemProperty -Path .\IsReadOnlyTextFile.txt -Name IsReadOnly -Value $True
Get-ChildItem -Path .\IsReadOnlyTextFile.txt
Add-Content -Path .\IsReadOnlyTextFile.txt -Value 'Add value to read-only text file' -Force
Get-Content -Path .\IsReadOnlyTextFile.txt

Mode                LastWriteTime         Length Name
----                -------------         ------ ----
-ar--         1/28/2019     13:35              0 IsReadOnlyTextFile.txt
  • The New-Item cmdlet uses the Path and ItemType parameters to create the file IsReadOnlyTextFile.txt in the current directory.
  • The Set-ItemProperty cmdlet uses the Name and Value parameters to change the file's IsReadOnly property to True.
  • The Get-ChildItem cmdlet shows the file is empty (0) and has the read-only attribute (r).
  • The Add-Content cmdlet uses the Path parameter to specify the file. The Value parameter includes the text string to append to the file. The Force parameter writes the text to the read-only file.
  • The Get-Content cmdlet uses the Path parameter to display the file's contents.

To remove the read-only attribute, use the Set-ItemProperty command with the Value parameter set to False.

Example 7: Use Filters with Add-Content

You can specify a filter to the Add-Content cmdlet. When using filters to qualify the Path parameter, you need to include a trailing asterisk (*) to indicate the contents of the path.

The following command adds the word "Done" the content of all *.txt files in the C:\Temp directory.

Add-Content -Path C:\Temp\* -Filter *.txt -Value "Done"

Parameters

-AsByteStream

Specifies that the content should be read as a stream of bytes. This parameter was introduced in PowerShell 6.0.

A warning occurs when you use the AsByteStream parameter with the Encoding parameter. The AsByteStream parameter ignores any encoding and the output is returned as a stream of bytes.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Confirm

Prompts you for confirmation before running the cmdlet.

Type:SwitchParameter
Aliases:cf
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Credential

Note

This parameter is not supported by any providers installed with PowerShell. To impersonate another user, or elevate your credentials when running this cmdlet, use Invoke-Command.

Type:PSCredential
Position:Named
Default value:None
Required:False
Accept pipeline input:True
Accept wildcard characters:False

-Encoding

Specifies the type of encoding for the target file. The default value is utf8NoBOM.

Encoding is a dynamic parameter that the FileSystem provider adds to the Add-Content cmdlet. This parameter works only in file system drives.

The acceptable values for this parameter are as follows:

  • ascii: Uses the encoding for the ASCII (7-bit) character set.
  • bigendianunicode: Encodes in UTF-16 format using the big-endian byte order.
  • bigendianutf32: Encodes in UTF-32 format using the big-endian byte order.
  • oem: Uses the default encoding for MS-DOS and console programs.
  • unicode: Encodes in UTF-16 format using the little-endian byte order.
  • utf7: Encodes in UTF-7 format.
  • utf8: Encodes in UTF-8 format.
  • utf8BOM: Encodes in UTF-8 format with Byte Order Mark (BOM)
  • utf8NoBOM: Encodes in UTF-8 format without Byte Order Mark (BOM)
  • utf32: Encodes in UTF-32 format.

Beginning with PowerShell 6.2, the Encoding parameter also allows numeric IDs of registered code pages (like -Encoding 1251) or string names of registered code pages (like -Encoding "windows-1251"). For more information, see the .NET documentation for Encoding.CodePage.

Note

UTF-7* is no longer recommended to use. As of PowerShell 7.1, a warning is written if you specify utf7 for the Encoding parameter.

Type:Encoding
Accepted values:ASCII, BigEndianUnicode, BigEndianUTF32, OEM, Unicode, UTF7, UTF8, UTF8BOM, UTF8NoBOM, UTF32
Position:Named
Default value:UTF8NoBOM
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Exclude

Specifies, as a string array, an item or items that this cmdlet excludes in the operation. The value of this parameter qualifies the Path parameter. Enter a path element or pattern, such as *.txt. Wildcard characters are permitted. The Exclude parameter is effective only when the command includes the contents of an item, such as C:\Windows\*, where the wildcard character specifies the contents of the C:\Windows directory.

Type:String[]
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:True

-Filter

Specifies a filter to qualify the Path parameter. The FileSystem provider is the only installed PowerShell provider that supports the use of filters. You can find the syntax for the FileSystem filter language in about_Wildcards. Filters are more efficient than other parameters, because the provider applies them when the cmdlet gets the objects rather than having PowerShell filter the objects after they are retrieved.

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:True

-Force

Overrides the read-only attribute, allowing you to add content to a read-only file. For example, Force overrides the read-only attribute but it does not change file permissions.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Include

Specifies, as a string array, an item or items that this cmdlet includes in the operation. The value of this parameter qualifies the Path parameter. Enter a path element or pattern, such as "*.txt". Wildcard characters are permitted. The Include parameter is effective only when the command includes the contents of an item, such as C:\Windows\*, where the wildcard character specifies the contents of the C:\Windows directory.

Type:String[]
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:True

-LiteralPath

Specifies a path to one or more locations. The value of LiteralPath is used exactly as it is typed. No characters are interpreted as wildcards. If the path includes escape characters, enclose it in single quotation marks. Single quotation marks tell PowerShell not to interpret any characters as escape sequences.

For more information, see about_Quoting_Rules.

Type:String[]
Aliases:PSPath, LP
Position:Named
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:False

-NoNewline

Indicates that this cmdlet does not add a new line or carriage return to the content.

The string representations of the input objects are concatenated to form the output. No spaces or newlines are inserted between the output strings. No newline is added after the last output string.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-PassThru

Returns an object representing the added content. By default, this cmdlet does not generate any output.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Path

Specifies the path to the items that receive the additional content. Wildcard characters are permitted. The paths must be paths to items, not to containers. For example, you must specify a path to one or more files, not a path to a directory. If you specify multiple paths, use commas to separate the paths.

Type:String[]
Position:0
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:True

-Stream

Note

This Parameter is only available on Windows.

Specifies an alternative data stream for content. If the stream does not exist, this cmdlet creates it. Wildcard characters are not supported.

Stream is a dynamic parameter that the FileSystem provider adds to Add-Content. This parameter works only in file system drives.

You can use the Add-Content cmdlet to change the content of any alternate data stream, such as Zone.Identifier. However, we do not recommend this as a way to eliminate security checks that block files that are downloaded from the Internet. If you verify that a downloaded file is safe, use the Unblock-File cmdlet.

This parameter was introduced in PowerShell 3.0.

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Value

Specifies the content to be added. Type a quoted string, such as This data is for internal use only, or specify an object that contains content, such as the DateTime object that Get-Date generates.

You cannot specify the contents of a file by typing its path, because the path is just a string. You can use a Get-Content command to get the content and pass it to the Value parameter.

Type:Object[]
Position:1
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:False

-WhatIf

Shows what would happen if the cmdlet runs. The cmdlet is not run.

Type:SwitchParameter
Aliases:wi
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

Inputs

System.Object, System.Management.Automation.PSCredential

You can pipe values, paths, or credentials to Set-Content.

Outputs

None or System.String

When you use the PassThru parameter, Add-Content generates a System.String object that represents the content. Otherwise, this cmdlet does not generate any output.

Notes

  • When you pipe an object to Add-Content, the object is converted to a string before it is added to the item. The object type determines the string format, but the format might be different than the default display of the object. To control the string format, use the formatting parameters of the sending cmdlet.
  • You can also refer to Add-Content by its built-in alias, ac. For more information, see about_Aliases.
  • The Add-Content cmdlet is designed to work with the data exposed by any provider. To list the providers available in your session, type Get-PSProvider. For more information, see about_Providers.