使用PowerShell按日期筛选文件夹

Question

I am going through folders we have on a work drive that have files over 20 years old in them. We want to move these files off this drive to clear up room and organize it better.

I have a PowerShell script to look through the folders and output to a csv file.

It puts into the csv file but there are thousands of files here. We only want to have the file with the latest modified on there. It is giving me every file.

Can I have it only output the latest modified file from that folder and then move onto the next folder?

Get-ChildItem -LiteralPath Y:\XYZ\MainFolder -Recurse -Depth 2  |Format-Table| Out-File C:\Users\USER\Desktop\aCSVfile.csv

Answer 1

You'll need PowerShell 5.x otherwise, the -Directory switch of Get-ChildItem will not be available:

Get-ChildItem -Path . -Directory -Recurse | Where-Object { $_.LastWriteTime -lt (Get-Date "2018-10-04") } | Export-Csv "test.csv" -NoTypeInformation -Delimiter ";"

• Get-ChildItem -Path . -Directory -Recurse Get-ChildItem -Path . -Directory -Recurse - Get all directories
• Where-Object { $_.LastWriteTime -lt (Get-Date "2018-10-04") } - check if the last write time is older than 2018-10-04 (you may also use LastAccessTime )
• Export-Csv "test.csv" -NoTypeInformation -Delimiter ";" - exports the filtered objects to CSV file.

If you want less information in the CSV file you can use Select-Object :

Get-ChildItem -Path . -Directory -Recurse | Where-Object { $_.LastWriteTime -lt (Get-Date "2018-10-04") } |Select-Object Name, PSPath, Parent | Export-Csv "test.csv" -NoTypeInformation -Delimiter ";"          

To get available properties use Get-Member :

 Get-ChildItem -Path . -Directory -Recurse | Where-Object { $_.LastWriteTime -lt (Get-Date "2018-10-04") } | Get-Member

Output:

    TypeName: System.IO.DirectoryInfo

    Name                      MemberType     Definition
    ----                      ----------     ----------
    LinkType                  CodeProperty   System.String LinkType{get=GetLinkType;}
    Mode                      CodeProperty   System.String Mode{get=Mode;}
    ... 
    FullName                  Property       string FullName {get;}
    LastAccessTime            Property       datetime LastAccessTime {get;set;}
    LastAccessTimeUtc         Property       datetime LastAccessTimeUtc {get;set;}
    LastWriteTime             Property       datetime LastWriteTime {get;set;}
    LastWriteTimeUtc          Property       datetime LastWriteTimeUtc {get;set;}
    Name                      Property       string Name {get;}
    ...
    Attributes                Property       System.IO.FileAttributes Attributes {get;set;}
    CreationTime              Property       datetime CreationTime {get;set;}
    CreationTimeUtc           Property       datetime CreationTimeUtc {get;set;}
    ...

From here you can use the *Property member types in Select-Object and Where-Object .

If you are on PowerShell less than 5, you've to check the PSIsContainer property, as explained in this stackoverflow answer .

Hope that's the information you're looking for.