How to remove a piece of a string after a certain character?

Question

PowerShell

Good afternoon, please help, it is necessary to remove the characters after the # sign in the xml file. The number of characters is always the same.
Example:
<ID>df1eaa47-6d9b-11e1-8016-000e0c4358bd#efc75a38-1e91-11e7-aacc-001d607884abID>
You need to remove the characters after # (including #) to get this:
<ID>df1eaa47-6d9b-11e1-8016- 000e0c4358bdID>
$str = Get-Content ''
$str.Split("ID>")[-1]
But that's not correct

Answer 1

(gc $fileName -raw) -replace '#.*',''

Answer 2

$obj = "<Ид>df1eaa47-6d9b-11e1-8016-000e0c4358bd#efc75a38-1e91-11e7-aacc-001d607884abИд>"
([regex]::matches($obj,"(<Ид>.*)#.*"))[0].groups[1].value + "Ид>"

Answer 3

$str = '<Ид>df1eaa47-6d9b-11e1-8016-000e0c4358bd#efc75a38-1e91-11e7-aacc-001d607884abИд>'
$str = $str.remove($str.indexof('#'))+"Ид>"