how can i store the basename of an item of an array ( i need to cmpare it later) in powershell

$DirVan="C:\BestandVerplaatsen\van\*"

DirNa="C:\BestandVerplaatsen\naar"

#$File = Get-ChildItem C:\BestandVerplaatsen\van\*.* # HELP !! --> this is still an object wich contains an array

#I need an object wich contains an item of that array because i need to compare it later with an array i can't compare it

#or i don't know how . for example there is a file without an exention. first it should check if directory olso go a file with the same name but with the exentention .xml (based on basename). if it exesits it should copy both files to another direcotry. if it doesn't exist it shoulgive a warning

$File

=???

#HELP how to get an object wich contains one item of the array

echo

$File

echo

""

#*******************************************************************

# Report baseName's

#*******************************************************************

#echo "basename wordt geplrint"

echo

"print basename of all files"

#get basename all files

$a

=gciC:\BestandVerplaatsen\van\*|% {$_.BaseName}

#$FilenameProper=$_.BaseName

$a

#echo whiteline

echo

""

#get basename xml files

echo

"print basename of .xml files" 

$b

=gciC:\BestandVerplaatsen\van\*-filter'*.xml'|% {$_.BaseName}

 $b

#*******************************************************************

# if files in directory copy to specific place

#*******************************************************************

($Filein$DirVan){

$exists=$DirVan|Where-Object {$_.BaseName -eq$_.BaseName}

# Help !!!

#what to fill in here because it needs to compare if there is a file in de directory with the same basename.

# if there is another file with the same basename it should execute some code below

if($exists

)

{

# execute code

}

}