Select Object - PowerShell

Overview

Select-Object extracts specific properties from objects in PowerShell, allowing you to filter and display only the desired data.

Syntax

Select-Object <Property1>, <Property2>, ... [<AdditionalParameters>]

Parameters

| Parameter | Description |
|—|—|
| Property1, Property2, ... | Properties to be selected. |
| -First <number> | Selects the first objects. |
| -Last <number> | Selects the last objects. |
| -Skip <number> | Skips the first objects. |
| -ExpandProperty <PropertyName> | Expands nested properties. |
| -Unique | Selects only unique objects. |

Options/Flags

  • -ExcludeProperty: Excludes specified properties.
  • -PassThru: Passes all objects through the pipeline with selected properties.
  • -ErrorAction: Specifies the action to be taken when an error occurs (default: Stop).
  • -WarningAction: Specifies the action to be taken when a warning occurs (default: Inquire).

Examples

Simple Selection

PS> Get-Process | Select-Object Name, Id

Complex Selection

PS> Get-Process | Select-Object -First 5 -Skip 2 -ExpandProperty PrivateMemory

Combining Options

PS> Get-EventLog -LogName System | Select-Object EventId, Source -ExcludeProperty TimeWritten -PassThru

Common Issues

  • Missing Property: If a specified property does not exist, an error will be thrown. Use -ErrorAction Ignore to suppress errors.
  • Data Truncation: If selected properties are too long, they may be truncated in the output. Use -ExpandProperty or increase terminal window width.

Integration

Select-Object can be chained with other commands for advanced filtering and processing:

Get-ChildItem | Select-Object -Unique | Where-Object { $_.LastWriteTime -lt (Get-Date).AddDays(-30) }