add function for fast search in pshell

Author: Bastien Perez - ITPro-Tips.com

Convert-ListToString.ps1

@@ -0,0 +1,14 @@
+function Convert-ListToString {
+    [CmdletBinding()]
+    param (
+        [Parameter()]
+        $InputArray
+    )
+
+    $string = New-Object -TypeName System.Text.StringBuilder
+    foreach ($object in $InputArray) {
+        [void]$string.Append($object)
+    }
+
+    return $string.ToString()
+}

Get-ObjectUnique.ps1

@@ -0,0 +1,9 @@
+function Get-ObjectUnique {
+    [CmdletBinding()]
+    param (
+        [Parameter()]
+        $InputArray
+    )
+
+    return [System.Collections.Generic.HashSet[string]]$InputArray
+}

Get-ObjectsInTwoArrays.ps1

@@ -0,0 +1,45 @@
+function Get-ObjectsInTwoArrays {
+    [CmdletBinding()]
+    param (
+        [Parameter()]
+        $Array,
+        [Parameter()]
+        $ArrayToCompare,
+        [Parameter(Mandatory)]
+        [ValidateSet('In', 'NotIn')]
+        $ComparisonMethod,
+        [Parameter(Mandatory)]
+        [ValidateSet('String', 'int','PSObject')]
+        $ObjectType
+    )
+    
+    if($ObjectType -eq 'String'){
+        $arrayIndex = [System.Collections.Generic.HashSet[String]]$Array
+    }
+    elseif($ObjectType -eq 'int'){
+        $arrayIndex = [System.Collections.Generic.HashSet[int]]$Array
+    }
+    elseif($ObjectType -eq 'PSObject'){
+        $arrayIndex = [System.Collections.Generic.HashSet[PSObject]]$Array
+    }
+    
+    [System.Collections.Generic.List[PSObject]]$res = @()
+
+    if ($ComparisonMethod -eq 'In') {
+        foreach ($object in $ArrayToCompare) {
+            if ($arrayIndex.Contains($object)) {
+                $res.Add($object)
+            }
+        }
+    }
+    elseif ($ComparisonMethod -eq 'NotIn') {
+        foreach ($object in $ArrayToCompare) {
+            if (-not($arrayIndex.Contains($object))) {
+                $res.Add($object)
+            }
+        }
+    }
+
+    Write-Host "$($res.count) $ComparisonMethod two arrays"
+    return $res
+}