使用 powershell 从目录中获取唯一扩展名的数量

Question

I'm trying to make a powershell script that can be placed into a directory and then return all of the unique extensions and their respective counts. Based on which extensions are found then I can output that information back. Whenever I run the script in its current state the CSV is created and imported but I cannot seem to pass the variables back from the CSV. If I make (Extension = "something") it will always output as true even when it shouldn't be, such is the case shown in code below for.jsp which is not in the directory and should not return anything. I am also unsure of how to measure the count of each extension as Measure-Object doesn't seem to be triggering properly.

My goals are as follows:

1. Grab all unique extensions and their count then place into CSV

2. Import from CSV all unique extensions and output a message if a specific extension is found along with the number of times it appears

$path = "C:\Users\spawn\Desktop\Powershell"

gci -rec $path -exclude *.ps1, *.csv, *.bat | Select-Object Extension -u | Export-Csv .\Export.csv
#Below is an example of how I think it should work
#gci -rec $path -exclude *.ps1, *.csv, *.bat | Measure-Object Extension | Export-Csv .\Export.csv

$escv = Import-Csv "C:\Users\spawn\Desktop\Powershell\Export.csv" 

ForEach ($data in $escv)
{
    $Count = $data.count
    $Extension = $data.extension
    
    if ($Extension -eq ".cs")
    {
        echo "A .cs file was found."
        echo "There were $Count files found."
    }
    if ($Extension -eq ".sln")
    {
        echo "A .sln file was found."
        echo "There were $Count files found."
    }
    if ($Extension -eq ".java")
    {
        echo "A .java file was found."
        echo "There were $Count files found."
    }
    if ($Extension -eq ".jsp")
    {
        echo "A .jsp file was found."
        echo "There were $Count files found."
    }
    return

}

Answer 1

Is there a reason to handle all possible extensions rather than loop through the list?

Group-Object gives you simple counts without loops.

You can re-use the same variable for writing to csv and screen.

$Path = 'C:\Users\spawn\Desktop\Powershell'
$ExcludeExtensions = @('*.ps1', '*.csv', '*.bat')

$Counts = Get-ChildItem -Recurse $Path -Exclude $ExcludeExtensions |
    Group-Object -Property Extension |
    Select-Object -Property @('Count', 'Name')
    
$Counts.ForEach{
    Write-Output "A $($_.Name) file was found"
    Write-Output "There were $($_.Count) files found"
}

$Counts | Export-Csv -LiteralPath (Join-Path $Path 'Export.csv')

Answer 2

With a hash:

dir | % { $hash = @{} } { $hash[$_.extension]++ }
$hash

Name                           Value
----                           -----
.exe                           5
.txt                           26
.vbs                           1
.vbs~                          1
.ps1#                          1
.nbi                           1
.spss                          1
.csv                           7
.android                       1
.csv#                          1
.json                          5
.bat                           5
.json~                         3
.iso                           1
.cisco                         1
.ps1                           22
.matplotlib                    1
.vscode                        1
.bat~                          1
.d                             1
.ps1~                          13
.eclipse                       1
.log                           50
.oracle_jre_usage              1
.emacs                         1
.xml~                          1
.tooling                       1
.pyosf                         1