powershell - Find Available Drive Letter and Change -

i trying create powershell script find available drive letter, map network drive, , change mapped drive. found following mapped \\server\share d: drive:

$drive = new-psdrive -name $(for($j=67;gdr($d=[char]$j++)2>0){}$d) -psprovider filesystem -root \\server\share\ 

i can manually enter d:, how can change in script? thinking along lines of this:

$drive = $drive.trim(":") 

but statement above throws following error:

method invocation failed because [system.management.automation.psdriveinfo] not contain method named 'trim'. @ line:1 char:1 + $drive = $drive.trim(":") + ~~~~~~~~~~~~~~~~~~~~~~~~~     + categoryinfo          : invalidoperation: (:) [], runtimeexception     + fullyqualifiederrorid : methodnotfound 

you check list of potential drive letters against list of assigned drive letters , use first unused one:

$used  = get-psdrive | select-object -expand name |          where-object { $_.length -eq 1 } $drive = 90..65 | foreach-object { [string][char]$_ } |          where-object { $used -notcontains $_ } |          select-object -first 1  new-psdrive -name $drive -psprovider filesystem -root \\server\share  set-location "${drive}:" 

or random 1 list:

$used   = get-psdrive | select-object -expand name |           where-object { $_.length -eq 1 } $unused = 90..65 | foreach-object { [string][char]$_ } |           where-object { $used -notcontains $_ } $drive  = $unused[(get-random -minimum 0 -maximum $unused.count)]  new-psdrive -name $drive -psprovider filesystem -root \\server\share  set-location "${drive}:"