Import-ExcelExtended HeaderName functionality

Examples/Import-ExcelWithHeaderName.ps1

@@ -0,0 +1,22 @@
+# Create Test File
+$path = "$env:TEMP\Test.xlsx"
+Remove-item -Path $path  -ErrorAction SilentlyContinue
+$processes = Get-Process | Select-Object -First 10
+$Processes | Export-Excel $path
+
+# Import the file as is.
+Import-Excel -Path $path | Format-Table
+# Import the file replacing the name of the 2 first headers and discarding the rest.
+Import-Excel -Path $path -HeaderName 'NewA', 'NewB'
+# Import the file selecting 3 of it's columns by name, renaming 2, changing the order and discarding the rest.
+Import-Excel -Path $path -HeaderName ([Ordered]@{Name = 'Process Name' ; StartTime = 'Start'; Path = 'Path'})
+<# Output Example:
+Process Name         Start               Path
+------------         -----               ----
+ApplicationFrameHost 07/04/2019 11:02:19 C:\WINDOWS\system32\ApplicationFrameHost.exe
+AppVShNotify
+audiodg              08/04/2019 19:21:32
+chrome               08/04/2019 16:49:47 C:\Program Files (x86)\Google\Chrome\Application\chrome.exe
+chrome               08/04/2019 16:49:27 C:\Program Files (x86)\Google\Chrome\Application\chrome.exe
+chrome               08/04/2019 16:49:27 C:\Program Files (x86)\Google\Chrome\Application\chrome.exe
+#>

ImportExcel.psm1

@@ -273,7 +273,7 @@ function Import-Excel {
         [ValidateNotNullOrEmpty()]
         [String]$WorksheetName,
         [Parameter(ParameterSetName = 'B', Mandatory)]
-        [String[]]$HeaderName ,
+        $HeaderName,
         [Parameter(ParameterSetName = 'C', Mandatory)]
         [Switch]$NoHeader     ,
         [Alias('HeaderRow', 'TopRow')]
@@ -312,7 +312,7 @@ function Import-Excel {
                         $C | Select-Object @{N = 'Column'; E = {$_}}, @{N = 'Value'; E = {'P' + $i}}
                     }
                 }
-                elseif ($HeaderName) {
+                elseif ($HeaderName -and $HeaderName -isnot [Collections.Hashtable] -and $HeaderName -isnot [Collections.Specialized.OrderedDictionary]) {
                     $i = 0
                     foreach ($H in $HeaderName) {
                         $H | Select-Object @{N = 'Column'; E = {$Columns[$i]}}, @{N = 'Value'; E = {$H}}
@@ -324,9 +324,18 @@ function Import-Excel {
                         throw 'The top row can never be equal to 0 when we need to retrieve headers from the worksheet.'
                     }
 
-                    foreach ($C in $Columns) {
+                    $PropertyNames = foreach ($C in $Columns) {
                         $Worksheet.Cells[$StartRow, $C] | Where-Object {$_.Value} | Select-Object @{N = 'Column'; E = {$C}}, Value
                     }
+
+                    if ($HeaderName) {
+                        foreach ($H in $HeaderName.GetEnumerator()) {
+                            $H | Select-Object @{N = 'Column'; E = {($PropertyNames | Where-Object {$_.Value -eq $H.Name}).Column}}, @{N = 'Value'; E = {$H.Value}}
+                        }
+                    }
+                    else {
+                        $PropertyNames
+                    }
                 }
             }
             Catch {