ConvertTo-Csv

Converts .NET objects into a series of character-separated value (CSV) strings.

Syntax

ConvertTo-Csv
              [-InputObject] <PSObject>
              [[-Delimiter] <Char>]
              [-IncludeTypeInformation]
              [-NoTypeInformation]
              [-QuoteFields <String[]>]
              [-UseQuotes <QuoteKind>]
              [<CommonParameters>]
ConvertTo-Csv
              [-InputObject] <PSObject>
              [-UseCulture]
              [-IncludeTypeInformation]
              [-NoTypeInformation]
              [-QuoteFields <String[]>]
              [-UseQuotes <QuoteKind>]
              [<CommonParameters>]

Description

The ConvertTo-CSV cmdlet returns a series of comma-separated value (CSV) strings that represent the objects that you submit. You can then use the ConvertFrom-Csv cmdlet to recreate objects from the CSV strings. The objects converted from CSV are string values of the original objects that contain property values and no methods.

You can use the Export-Csv cmdlet to convert objects to CSV strings. Export-CSV is similar to ConvertTo-CSV, except that it saves the CSV strings to a file.

The ConvertTo-CSV cmdlet has parameters to specify a delimiter other than a comma or use the current culture as the delimiter.

Examples

Example 1: Convert an object to CSV

This example converts a Process object to a CSV string.

Get-Process -Name pwsh | ConvertTo-Csv -NoTypeInformation

"Name","SI","Handles","VM","WS","PM","NPM","Path","Parent","Company","CPU","FileVersion", ...
"pwsh","8","950","2204001161216","100925440","59686912","67104", ...

The Get-Process cmdlet gets the Process object and uses the Name parameter to specify the PowerShell process. The process object is sent down the pipeline to the ConvertTo-CSV cmdlet. The ConvertTo-CSV cmdlet converts the object to CSV strings. The NoTypeInformation parameter removes the #TYPE information header from the CSV output and is not required in PowerShell 6.

Example 2: Convert a DateTime object to CSV

This example converts a DateTime object to a CSV string.

$Date = Get-Date
ConvertTo-Csv -InputObject $Date -Delimiter ';' -NoTypeInformation

"DisplayHint";"DateTime";"Date";"Day";"DayOfWeek";"DayOfYear";"Hour";"Kind";"Millisecond";"Minute";"Month";"Second";"Ticks";"TimeOfDay";"Year"
"DateTime";"Friday, January 4, 2019 14:40:51";"1/4/2019 00:00:00";"4";"Friday";"4";"14";"Local";"711";"40";"1";"51";"636822096517114991";"14:40:51.7114991";"2019"

The Get-Date cmdlet gets the DateTime object and saves it in the $Date variable. The ConvertTo-Csv cmdlet converts the DateTime object to strings. The InputObject parameter uses the DateTime object stored in the $Date variable. The Delimiter parameter specifies a semicolon to separate the string values. The NoTypeInformation parameter removes the #TYPE information header from the CSV output and is not required in PowerShell 6.

Example 3: Convert the PowerShell event log to CSV

This example converts the Windows event log for PowerShell to a series of CSV strings.

(Get-Culture).TextInfo.ListSeparator
Get-WinEvent -LogName 'PowerShellCore/Operational' | ConvertTo-Csv -UseCulture -NoTypeInformation

,
"Message","Id","Version","Qualifiers","Level","Task","Opcode","Keywords","RecordId", ...
"Error Message = System error""4100","1",,"3","106","19","0","31716","PowerShellCore", ...

The Get-Culture cmdlet uses the nested properties TextInfo and ListSeparator and displays the current culture's default list separator. The Get-WinEvent cmdlet gets the event log objects and uses the LogName parameter to specify the log file name. The event log objects are sent down the pipeline to the ConvertTo-Csv cmdlet. The ConvertTo-Csv cmdlet converts the event log objects to a series of CSV strings. The UseCulture parameter uses the current culture's default list separator as the delimiter. The NoTypeInformation parameter removes the #TYPE information header from the CSV output and is not required in PowerShell 6.

Example 4: Convert to CSV with quotes around two columns

This example converts a DateTime object to a CSV string.

Get-Date | ConvertTo-Csv -QuoteFields "DateTime","Date"

DisplayHint,"DateTime","Date",Day,DayOfWeek,DayOfYear,Hour,Kind,Millisecond,Minute,Month,Second,Ticks,TimeOfDay,Year
DateTime,"Thursday, August 22, 2019 11:27:34 AM","8/22/2019 12:00:00 AM",22,Thursday,234,11,Local,569,27,8,34,637020700545699784,11:27:34.5699784,2019

Example 5: Convert to CSV with quotes only when needed

This example converts a DateTime object to a CSV string.

Get-Date | ConvertTo-Csv -UseQuotes AsNeeded

DisplayHint,DateTime,Date,Day,DayOfWeek,DayOfYear,Hour,Kind,Millisecond,Minute,Month,Second,Ticks,TimeOfDay,Year
DateTime,"Thursday, August 22, 2019 11:31:00 AM",8/22/2019 12:00:00 AM,22,Thursday,234,11,Local,713,31,8,0,637020702607132640,11:31:00.7132640,2019

Example 6: Convert hashtables to CSV

In PowerShell 7.2 and above, when you convert hashtables to CSV, the keys of the first hashtable are serialized and used as headers in the output.

$person1 = @{
    Name = 'John Smith'
    Number = 1
}

$person2 = @{
    Name = 'Jane Smith'
    Number = 1
}

$allPeople = $person1, $person2
$allPeople | ConvertTo-Csv

"Name","Number"
"John Smith","1"
"Jane Smith","2"

Example 7: Converting hashtables to CSV with additional properties

In PowerShell 7.2 and above, when you convert a hashtable that has additional properties added with Add-Member or Select-Object the additional properties are also added as a header in the CSV output.

$allPeople | Add-Member -Name ExtraProp -Value 42
$allPeople | ConvertTo-Csv

"Name","Number","ExtraProp"
"John Smith","1","42"
"Jane Smith","2","42"

Each hashtable has a property named ExtraProp added by Add-Member and then converted to CSV. You can see ExtraProp is now a header in the output.

If an added property has the same name as a key from the hashtable, the key takes precedence and only the key is converted to CSV.

Parameters

-Delimiter

Specifies the delimiter to separate the property values in CSV strings. The default is a comma (,). Enter a character, such as a colon (:). To specify a semicolon (;) enclose it in single quotation marks.

Type:Char
Position:1
Default value:comma (,)
Accept pipeline input:False
Accept wildcard characters:False
-IncludeTypeInformation

When this parameter is used the first line of the output contains #TYPE followed by the fully qualified name of the object type. For example, #TYPE System.Diagnostics.Process.

This parameter was introduced in PowerShell 6.0.

Type:SwitchParameter
Aliases:ITI
Position:Named
Default value:#TYPE <Object>
Accept pipeline input:False
Accept wildcard characters:False
-InputObject

Specifies the objects that are converted to CSV strings. Enter a variable that contains the objects or type a command or expression that gets the objects. You can also pipe objects to ConvertTo-CSV.

Type:PSObject
Position:0
Default value:None
Accept pipeline input:True
Accept wildcard characters:False
-NoTypeInformation

Removes the #TYPE information header from the output. This parameter became the default in PowerShell 6.0 and is included for backwards compatibility.

Type:SwitchParameter
Aliases:NTI
Position:Named
Default value:None
Accept pipeline input:False
Accept wildcard characters:False
-QuoteFields

Specifies the names of the columns that should be quoted. When this parameter is used only the specified columns are quoted. This parameter was added in PowerShell 7.0.

Type:String[]
Aliases:QF
Position:Named
Default value:None
Accept pipeline input:False
Accept wildcard characters:False
-UseCulture

Uses the list separator for the current culture as the item delimiter. To find the list separator for a culture, use the following command: (Get-Culture).TextInfo.ListSeparator.

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

Specifies when quotes are used in the CSV files. Possible values are:

  • Never - don't quote anything
  • Always - quote everything (default behavior)
  • AsNeeded - only quote fields that contain a delimiter character, double-quote, or newline character

This parameter was added in PowerShell 7.0.

Type:Microsoft.PowerShell.Commands.BaseCsvWritingCommand+QuoteKind
Aliases:UQ
Position:Named
Default value:Always
Accept pipeline input:False
Accept wildcard characters:False

Inputs

PSObject

You can pipe any object that has an Extended Type System (ETS) adapter to ConvertTo-CSV.

Outputs

String

The CSV output is returned as a collection of strings.

Notes

In CSV format, each object is represented by a comma-separated list of its property value. The property values are converted to strings using the object's ToString() method. The strings are represented by the property value name. ConvertTo-CSV does not export the object's methods.

The CSV strings are output as follows:

  • If IncludeTypeInformation is used, the first string consists of #TYPE followed by the object type's fully qualified name. For example, #TYPE System.Diagnostics.Process.
  • If IncludeTypeInformation is not used the first string includes the column headers. The headers contain the first object's property names as a comma-separated list.
  • The remaining strings contain comma-separated lists of each object's property values.

Beginning with PowerShell 6.0 the default behavior of ConvertTo-CSV is to not include the #TYPE information in the CSV and NoTypeInformation is implied. IncludeTypeInformation can be used to include the #TYPE information and emulate the default behavior of ConvertTo-CSV prior to PowerShell 6.0.

When you submit multiple objects to ConvertTo-CSV, ConvertTo-CSV orders the strings based on the properties of the first object that you submit. If the remaining objects do not have one of the specified properties, the property value of that object is Null, as represented by two consecutive commas. If the remaining objects have additional properties, those property values are ignored.