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Write-Output

  • Reference
Module:
Microsoft.PowerShell.Utility

Writes the specified objects to the pipeline.

Syntax

Write-Output
     [-InputObject] <PSObject[]>
     [-NoEnumerate]
     [<CommonParameters>]

Description

Writes the specified objects to the pipeline. If Write-Output is the last command in the pipeline, the objects are displayed in the console.

Write-Output sends objects to the primary pipeline, also known as the success stream. To send error objects to the error stream, use Write-Error.

This cmdlet is typically used in scripts to display strings and other objects on the console. One of the built-in aliases for Write-Output is echo and similar to other shells that use echo. The default behavior is to display the output at the end of a pipeline. In PowerShell, it is generally not necessary to use the cmdlet in instances where the output is displayed by default. For example, Get-Process | Write-Output is equivalent to Get-Process. Or, echo "Home directory: $HOME" can be written, "Home directory: $HOME".

By default, Write-Output enumerates objects in a collection. However, Write-Output can also pass collections down the pipeline as a single object with the NoEnumerate parameter.

Examples

Example 1: Get objects and write them to the console

In this example, the results of the Get-Process cmdlet are stored in the $P variable. The Write-Output cmdlet displays the process objects in $P to the console.

$P = Get-Process
Write-Output $P

Example 2: Pass output to another cmdlet

This command pipes the "test output" string to the Get-Member cmdlet, which displays the members of the System.String class, demonstrating that the string was passed along the pipeline.

Write-Output "test output" | Get-Member

Example 3: Suppress enumeration in output

This command adds the NoEnumerate parameter to treat a collection or array as a single object through the pipeline.

Write-Output 1,2,3 | Measure-Object

Count    : 3
...

Write-Output 1,2,3 -NoEnumerate | Measure-Object

Count    : 1
...

Parameters

-InputObject

Specifies the objects to send down the pipeline. Enter a variable that contains the objects, or type a command or expression that gets the objects.

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

-NoEnumerate

By default, the Write-Output cmdlet always enumerates its output. The NoEnumerate parameter suppresses the default behavior, and prevents Write-Output from enumerating output. The NoEnumerate parameter has no effect if the command is wrapped in parentheses, because the parentheses force enumeration. For example, (Write-Output 1,2,3 -NoEnumerate) still enumerates the array.

The NoEnumerate parameter is only useful within a pipeline. Trying to see the effects of NoEnumerate in the console is problematic because PowerShell adds Out-Default to the end of every command line, which results in enumeration. But if you pipe Write-Output -NoEnumerate to another cmdlet, the downstream cmdlet receives the collection object, not the enumerated items of the collection.

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

Inputs

PSObject

You can pipe objects to this cmdlet.

Outputs

PSObject

This cmdlet returns the objects that are submitted as input.

Notes

PowerShell includes the following aliases for Write-Output:

  • All platforms:

    • echo

  • Windows:

    • write