How to change the value of XML Element attribute using PowerShell?

Try the following:

$nodes = $xml.SelectNodes("/office/staff");foreach($node in $nodes) {    $node.SetAttribute("branch", "New York");}

This will iterate through all nodes returned by SelectNodes() and modify each one.

You can access the attributes directly in the [xml] object like this:

# C:\temp> $xml = [xml](Get-Content C:\FE6Work.xml)# C:\temp> $xml.office.staffbranch                   Type                           employee                                                             ------                   ----                           --------                                                             Hanover                  sales                          {Tobias Weltner, Cofi Heidecke}                                      London                   Technology                     {XXXX, Cofi}                                                         # C:\temp> $xml.office.staff | foreach{$_.branch = "New York"}# C:\temp> $xml.office.staffbranch                   Type                           employee                                                             ------                   ----                           --------                                                             New York                 sales                          {Tobias Weltner, Cofi Heidecke}                                      New York                 Technology                     {XXXX, Cofi}                                                         

if we are taking attribute from console and changing its value ?

$path=Read-Host -Prompt 'Enter path of xml file'[xml]$xmldata = get-content "$path"$tag = Read-Host -Prompt 'Enter tag'$value = Read-Host -Prompt 'Enter value'$xmldata.InstallConfig.$tag="$value"$xmldata.Save($path)