Replace placeholders with actual values in PowerShell dictionary

问题

Following is the sample xml file:

 <configuration>
  <environment id="Development">
    <type>Dev</type>
    <client>Arizona</client>
    <dataSource>Local</dataSource>
    <path>App_Data\%%type%%\%%client%%_%%dataSource%%</path>
    <targetmachines>
      <targetmachine>
        <name>Any</name>
        <remotedirectory>D:\Inetpub\Test</remotedirectory>
      </targetmachine>
    </targetmachines>
  </environment>
 </configuration>

I'm trying to convert the above xml file into a PowerShell dictionary using following script.

[System.Xml.XmlDocument] $configxml = Get-Content xmlfile
$environmentId = "Development"
$keyValuePairs = New-Object "System.Collections.Generic.Dictionary``2[System.String,System.String]"
$configxml.SelectNodes("//configuration/environment[@id='$($environmentId)']//*[not(*)]") | `
    ForEach-Object {
                    if($_.ParentNode.ToString() -ne "targetmachine")
                    {

                        $keyValuePairs.Add($_.Name.ToLower(), $_.InnerText)
                    }
                }

Write-Output $keyValuePairs

Im getting following output, which is expected.

Key                         Value
-----                       -----
type                        Dev
client                      Arizona
dataSource                  Local
path                        App_Data\%%type%%\%%client%%_%%dataSource%%

But After converting the elements into Key value pairs, I want to replace the placeholders with actualy values. In other words, element "Path" has 3 placeholders, they are

1. type
2. client
3. dataSource

Basically placeholders means the strings which starts and ends with two percents (%%xyz%%). So, I need following output after replacing placeholders with actual values:

Key                         Value
-----                       -----
type                        Dev
client                      Arizona
dataSource                  Local
path                        App_Data\Dev\Arizona_Local

Can someone please help me how can I achive this using PowerShell. Thanks in advance.

回答1:

In general, when posting an example with xml or csv data, it is helpful to use here strings to represent the data instead of referencing a file that others do not have.

Something like this can be used to achieve your result.

$xmldata = @"
<configuration>
    <environment id="Development">
    <type>Dev</type>
    <client>Arizona</client>
    <dataSource>Local</dataSource>
    <path>App_Data\%%type%%\%%client%%_%%dataSource%%</path>
    <targetmachines>
        <targetmachine>
        <name>Any</name>
        <remotedirectory>D:\Inetpub\Test</remotedirectory>
        </targetmachine>
    </targetmachines>
    </environment>
</configuration>
"@

[System.Xml.XmlDocument] $configxml = [xml]$xmldata
$environmentId = "Development"
$keyValuePairs = New-Object "System.Collections.Generic.Dictionary``2[System.String,System.String]"
$configxml.SelectNodes("//configuration/environment[@id='$($environmentId)']//*[not(*)]") | `
    ForEach-Object {
                    if($_.ParentNode.ToString() -ne "targetmachine")
                    {

                        $keyValuePairs.Add($_.Name, $_.InnerText)
                    }
                }

"BEFORE---->"
Write-Output $keyValuePairs

# A static way...
#$keyValuePairs.path = $keyValuePairs.path -replace '%%type%%', $keyValuePairs.type
#$keyValuePairs.path = $keyValuePairs.path -replace '%%client%%', $keyValuePairs.client
#$keyValuePairs.path = $keyValuePairs.path -replace '%%datasource%%', $keyValuePairs.datasource

# Something more dynamic
$m = [Regex]::Matches($keyValuePairs.path,"%%(.+?)%%*")
$m | % {
    $tag = $_.Groups[1].Value
    $keyValuePairs.path = $keyValuePairs.path -replace "%%$tag%%", $($keyValuePairs.$tag)
}

"AFTER---->"
Write-Output $keyValuePairs

Note, if you wanted something totally dynamic in nature, it can be done by getting all the placeholders by some other method, like a regex with capture, but that seemed unnecessary based on the problem statement.

来源：https://stackoverflow.com/questions/42661150/replace-placeholders-with-actual-values-in-powershell-dictionary

标签

xml

powershell

dictionary

powershell-2.0