Import-CSV
Applies To: Windows PowerShell 2.0
Converts object properties in a comma-separated value (CSV) file into CSV versions of the original objects.
Syntax
Import-CSV [[-Delimiter] <char>] [-Path] <string[]> [-Header <string[]>] [<CommonParameters>]
Import-CSV -UseCulture [-Path] <string[]> [-Header <string[]>] [<CommonParameters>]
Description
The Import-CSV cmdlet creates objects from CSV variable-length files that are generated by the Export-CSV cmdlet.
You can use the parameters of the Import-CSV cmdlet to specify the column header row, which determines the property names of the resulting objects; to specify the item delimiter; or to direct Import-CSV to use the list separator for the current culture as the item delimiter.
The objects that Import-CSV creates are CSV versions of the original objects. The property values of the CSV objects are string versions of the property values of the original objects. The CSV versions of the objects do not have any methods.
You can also use the ConvertTo-CSV and ConvertFrom-CSV cmdlets to convert objects to CSV strings (and back). These cmdlets are the same as the Export-CSV and Import-CSV cmdlets, except that they do not save the CSV strings in a file.
Parameters
-Delimiter <char>
Specifies the delimiter that separates the property values in the CSV file. The default is a comma (,). Enter a character, such as a colon (:). To specify a semicolon (;), enclose it in quotation marks.
If you specify a character other than the actual string delimiter in the file, Import-CSV cannot create objects from the CSV strings. Instead, it returns the strings.
Required? |
false |
Position? |
2 |
Default Value |
, |
Accept Pipeline Input? |
false |
Accept Wildcard Characters? |
false |
-Header <string[]>
Specifies an alternate column header row for the imported file. The column header determines the names of the properties of the object that Import-CSV creates.
Enter a comma-separated list of the column headers. Enclose each item in quotation marks (single or double). Do not enclose the header string in quotation marks. If you enter fewer column headers than there are columns, the remaining columns will have no header. If you enter more headers than there are columns, the extra headers are ignored.
When using the Header parameter, delete the original header row from the CSV file. Otherwise, Import-CSV creates an extra object from the items in the header row.
Required? |
false |
Position? |
named |
Default Value |
none |
Accept Pipeline Input? |
false |
Accept Wildcard Characters? |
false |
-Path <string[]>
Specifies the path to the CSV file to import. You can also pipe a path to Import-CSV.
Required? |
true |
Position? |
1 |
Default Value |
None |
Accept Pipeline Input? |
true (ByValue, ByPropertyName) |
Accept Wildcard Characters? |
false |
-UseCulture
Use the list separator for the current culture as the item delimiter. The default is a comma (,).
To find the list separator for a culture, use the following command: (Get-Culture).TextInfo.ListSeparator. If you specify a character other than the delimiter used in the CSV strings, ConvertFrom-CSV cannot create objects from the CSV strings. Instead, it returns the strings.
Required? |
true |
Position? |
named |
Default Value |
Comma |
Accept Pipeline Input? |
false |
Accept Wildcard Characters? |
false |
<CommonParameters>
This command supports the common parameters: Verbose, Debug, ErrorAction, ErrorVariable, OutBuffer, OutVariable, WarningAction, and WarningVariable. For more information, see about_CommonParameters.
Inputs and Outputs
The input type is the type of the objects that you can pipe to the cmdlet. The return type is the type of the objects that the cmdlet returns.
Inputs |
System.String You can pipe a string that contains a path to Import-CSV. |
Outputs |
Object. Import-CSV returns the objects described by the content in the CSV file. |
Notes
Because the imported objects are CSV versions of the object type, they are not recognized and formatted by the Windows PowerShell type formatting entries that format the non-CSV versions of the object type.
In the CSV file, each object is represented by a comma-separated list of the property values of the object. The property values are converted to strings (by using the ToString() method of the object), so they are generally represented by the name of the property value. Export-CSV does not export the methods of the object.
Example 1
C:\PS>get-process | export-csv processes.csv
C:\PS> $p = import-CSV processes.csv
C:\PS> $p | get-member
TypeName: CSV:System.Diagnostics.Process
Name MemberType Definition
---- ---------- ----------
Equals Method System.Boolean Equals(Object obj)
GetHashCode Method System.Int32 GetHashCode()
GetType Method System.Type GetType()
ToString Method System.String ToString()
BasePriority NoteProperty System.String BasePriority=8
Company NoteProperty System.String Company=Microsoft Corporation
...
C:\PS> $p | out-gridview
Description
-----------
This example shows how to export and then import a CSV file of Microsoft .NET Framework objects.
The first command uses the Get-Process cmdlet to get the process on the local computer. It uses a pipeline operator (|) to send the process objects to the Export-CSV cmdlet, which exports the process objects to the Processes.csv file in the current directory.
The second command uses the Import-CSV cmdlet to import the processes in the Import-CSV file. Then it saves the resulting process objects in the $p variable.
The third command uses a pipeline operator to pipe the imported objects to the Get-Member cmdlets. The result shows that they are CSV:System.Diagnostic.Process objects, not the System.Diagnostic.Process objects that Get-Process returns.
Also, because there is no entry type in the formatting files for the CSV version of the process objects, these objects are not formatted in the same way that standard process objects are formatted.
To display the objects, use the formatting cmdlets, such as Format-Table and Format-List, or pipe the objects to Out-GridView.
Example 2
C:\PS>get-process | export-csv processes.csv -Delimiter :
C:\PS> $p = import-csv processes.csv -Delimiter :
Description
-----------
This example shows how to use the Delimiter parameter of Import-CSV. In this example, the processes are exported to a file that uses a colon (:) as a delimiter.
When importing, the Import-CSV file uses the Delimiter parameter to indicate the delimiter that is used in the file.
Example 3
C:\PS>$p = import-csv processes.csv -UseCulture
C:\PS> (get-culture).textinfo.listseparator
,
Description
-----------
This example shows how to use the UseCulture parameter of Import-CSV.
The first command imports the objects in the Processes.csv file into the $p variable. It uses the UseCulture parameter to direct Import-CSV to use the list separator defined for the current culture.
The second command displays the list separator for the current culture. It uses the Get-Culture cmdlet to get the current culture. It uses the dot (.) method to get the TextInfo property of the current culture and the ListSeparator property of the object in TextInfo. In this example, the command returns a comma.
Example 4
C:\PS>start-job -scriptblock { get-process } | export-csv jobs.csv
C:\PS> $header = "MoreData","StatusMessage","Location","Command","State","Finished","InstanceId","SessionId","Name","ChildJobs","Output","Error","Progress","Verbose","Debug","Warning","StateChanged"
# Delete header from file
C:\PS> $a = (get-content jobs.csv)
C:\PS> $a = $a[0], $a[2..($a.count - 1)]
C:\PS> $a > jobs.csv
C:\PS> $j = import-csv jobs.csv -header $header
C:\PS> $j
MoreData : True
StatusMessage :
Location : localhost
Command : get-process
State : Running
Finished : System.Threading.ManualResetEvent
InstanceId : 135bdd25-40d6-4a20-bd68-05282a59abd6
SessionId : 1
Name : Job1
ChildJobs : System.Collections.Generic.List`1[System.Management.Automation.Job]
Output : System.Management.Automation.PSDataCollection`1[System.Management.Automation.PSObject]
Error : System.Management.Automation.PSDataCollection`1[System.Management.Automation.ErrorRecord]
Progress : System.Management.Automation.PSDataCollection`1[System.Management.Automation.ProgressRecord]
Verbose : System.Management.Automation.PSDataCollection`1[System.String]
Debug : System.Management.Automation.PSDataCollection`1[System.String]
Warning : System.Management.Automation.PSDataCollection`1[System.String]
StateChanged :
Description
-----------
This example shows how to use the Header parameter of Import-CSV to change the names of properties in the resulting imported object.
The first command uses the Start-Job cmdlet to start a background job that runs a Get-Process command on the local computer. A pipeline operator (|) sends the resulting job object to the Export-CSV cmdlet, which converts the job object to CSV format. An assignment operator (=) saves the resulting CSV in the Jobs.csv file.
The second command saves a header in the $header variable. Unlike the default header, this header uses "MoreData" instead of "HasMoreData" and "State" instead of "JobStateInfo".
The next three commands delete the original header (the second line) from the Jobs.csv file.
The sixth command uses the Import-CSV cmdlet to import the Jobs.csv file and convert the CSV strings into a CSV version of the job object. The command uses the Header parameter to submit the alternate header. The results are stored in the $j variable.
The seventh command displays the object in the $j variable. The resulting object has "MoreData" and "State" properties, as shown in the command output.
Example 5
C:\PS>".\processes.csv" | import-csv
Description
-----------
This command imports the objects from the Processes.csv file.