[powershell] How to convert string to integer in PowerShell

I have a list of directories with numbers. I have to find the highest number and and increment it by 1 and create a new directory with that increment value. I am able to sort the below array, but I am not able to increment the last element as it is a string.

How do I convert this below array element to an integer?

PS C:\Users\Suman\Desktop> $FileList

Name
----
11
2
1

Once you have selected the highest value, which is "12" in my example, you can then declare it as integer and increment your value:

$FileList = "1", "2", "11"
$foldername = [int]$FileList[2] + 1
$foldername

Use:

$filelist = @("11", "1", "2")
$filelist | sort @{expression={[int]$_}} | % {$newName = [string]([int]$_ + 1)}
New-Item $newName -ItemType Directory

Use:

$filelist = @(11, 1, 2)
$filelist | sort @{expression={$_[0]}} | 
  % {$newName = [string]([int]$($_[0]) + 1)}
  New-Item $newName -ItemType Directory

Example:

2.032 MB (2,131,022 bytes)

$u=($mbox.TotalItemSize.value).tostring()

$u=$u.trimend(" bytes)") #yields 2.032 MB (2,131,022

$u=$u.Split("(") #yields `$u[1]` as 2,131,022

$uI=[int]$u[1]

The result is 2131022 in integer form.