Example 1-18. Show-Object.ps1

############################################################################# ## ## Show-Object ## ## From Windows PowerShell Cookbook (O'Reilly) ## by Lee Holmes (http://www.leeholmes.com/guide) ## ############################################################################## <# .SYNOPSIS Provides a graphical interface to let you explore and navigate an object. .EXAMPLE PS > $ps = { Get-Process -ID $pid }.Ast PS > Show-Object $ps #> param( ## The object to examine [Parameter(ValueFromPipeline = $true)] $InputObject ) Set-StrictMode -Version 3 Add-Type -Assembly System.Windows.Forms ## Figure out the variable name to use when displaying the ## object navigation syntax. To do this, we look through all ## of the variables for the one with the same object identifier. $rootVariableName = dir variable:\* -Exclude InputObject,Args | Where-Object { $_.Value -and ($_.Value.GetType() -eq $InputObject.GetType()) -and ($_.Value.GetHashCode() -eq $InputObject.GetHashCode()) } ## If we got multiple, pick the first $rootVariableName = $rootVariableName| % Name | Select -First 1 ## If we didn't find one, use a default name if(-not $rootVariableName) { $rootVariableName = "InputObject" } ## A function to add an object to the display tree function PopulateNode($node, $object) { ## If we've been asked to add a NULL object, just return if(-not $object) { return } ## If the object is a collection, then we need to add multiple ## children to the node if([System.Management.Automation.LanguagePrimitives]::GetEnumerator($object)) { ## Some very rare collections don't support indexing (i.e.: $foo[0]). ## In this situation, PowerShell returns the parent object back when you ## try to access the [0] property. $isOnlyEnumerable = $object.GetHashCode() -eq $object[0].GetHashCode() ## Go through all the items $count = 0 foreach($childObjectValue in $object) { ## Create the new node to add, with the node text of the item and ## value, along with its type $newChildNode = New-Object Windows.Forms.TreeNode $newChildNode.Text = "$($node.Name)[$count] = $childObjectValue : " + $childObjectValue.GetType() ## Use the node name to keep track of the actual property name ## and syntax to access that property. ## If we can't use the index operator to access children, add ## a special tag that we'll handle specially when displaying ## the node names. if($isOnlyEnumerable) { $newChildNode.Name = "@" } $newChildNode.Name += "[$count]" $null = $node.Nodes.Add($newChildNode) ## If this node has children or properties, add a placeholder ## node underneath so that the node shows a '+' sign to be ## expanded. AddPlaceholderIfRequired $newChildNode $childObjectValue $count++ } } else { ## If the item was not a collection, then go through its ## properties foreach($child in $object.PSObject.Properties) { ## Figure out the value of the property, along with ## its type. $childObject = $child.Value $childObjectType = $null if($childObject) { $childObjectType = $childObject.GetType() } ## Create the new node to add, with the node text of the item and ## value, along with its type $childNode = New-Object Windows.Forms.TreeNode $childNode.Text = $child.Name + " = $childObject : $childObjectType" $childNode.Name = $child.Name $null = $node.Nodes.Add($childNode) ## If this node has children or properties, add a placeholder ## node underneath so that the node shows a '+' sign to be ## expanded. AddPlaceholderIfRequired $childNode $childObject } } } ## A function to add a placeholder if required to a node. ## If there are any properties or children for this object, make a temporary ## node with the text "..." so that the node shows a '+' sign to be ## expanded. function AddPlaceholderIfRequired($node, $object) { if(-not $object) { return } if([System.Management.Automation.LanguagePrimitives]::GetEnumerator($object) -or @($object.PSObject.Properties)) { $null = $node.Nodes.Add( (New-Object Windows.Forms.TreeNode "...") ) } } ## A function invoked when a node is selected. function OnAfterSelect { param($Sender, $TreeViewEventArgs) ## Determine the selected node $nodeSelected = $Sender.SelectedNode ## Walk through its parents, creating the virtual ## PowerShell syntax to access this property. $nodePath = GetPathForNode $nodeSelected ## Now, invoke that PowerShell syntax to retrieve ## the value of the property. $resultObject = Invoke-Expression $nodePath $outputPane.Text = $nodePath ## If we got some output, put the object's member ## information in the text box. if($resultObject) { $members = Get-Member -InputObject $resultObject | Out-String $outputPane.Text += "`n" + $members } } ## A function invoked when the user is about to expand a node function OnBeforeExpand { param($Sender, $TreeViewCancelEventArgs) ## Determine the selected node $selectedNode = $TreeViewCancelEventArgs.Node ## If it has a child node that is the placeholder, clear ## the placeholder node. if($selectedNode.FirstNode -and ($selectedNode.FirstNode.Text -eq "...")) { $selectedNode.Nodes.Clear() } else { return } ## Walk through its parents, creating the virtual ## PowerShell syntax to access this property. $nodePath = GetPathForNode $selectedNode ## Now, invoke that PowerShell syntax to retrieve ## the value of the property. Invoke-Expression "`$resultObject = $nodePath" ## And populate the node with the result object. PopulateNode $selectedNode $resultObject } ## A function to handle keypresses on the form. ## In this case, we capture ^C to copy the path of ## the object property that we're currently viewing. function OnKeyPress { param($Sender, $KeyPressEventArgs) ## [Char] 3 = Control-C if($KeyPressEventArgs.KeyChar -eq 3) { $KeyPressEventArgs.Handled = $true ## Get the object path, and set it on the clipboard $node = $Sender.SelectedNode $nodePath = GetPathForNode $node [System.Windows.Forms.Clipboard]::SetText($nodePath) $form.Close() } } ## A function to walk through the parents of a node, ## creating virtual PowerShell syntax to access this property. function GetPathForNode { param($Node) $nodeElements = @() ## Go through all the parents, adding them so that ## $nodeElements is in order. while($Node) { $nodeElements = ,$Node + $nodeElements $Node = $Node.Parent } ## Now go through the node elements $nodePath = "" foreach($Node in $nodeElements) { $nodeName = $Node.Name ## If it was a node that PowerShell is able to enumerate ## (but not index), wrap it in the array cast operator. if($nodeName.StartsWith('@')) { $nodeName = $nodeName.Substring(1) $nodePath = "@(" + $nodePath + ")" } elseif($nodeName.StartsWith('[')) { ## If it's a child index, we don't need to ## add the dot for property access } elseif($nodePath) { ## Otherwise, we're accessing a property. Add a dot. $nodePath += "." } ## Append the node name to the path $nodePath += $nodeName } ## And return the result $nodePath } ## Create the TreeView, which will hold our object navigation ## area. $treeView = New-Object Windows.Forms.TreeView $treeView.Dock = "Top" $treeView.Height = 500 $treeView.PathSeparator = "." $treeView.Add_AfterSelect( { OnAfterSelect @args } ) $treeView.Add_BeforeExpand( { OnBeforeExpand @args } ) $treeView.Add_KeyPress( { OnKeyPress @args } ) ## Create the output pane, which will hold our object ## member information. $outputPane = New-Object System.Windows.Forms.TextBox $outputPane.Multiline = $true $outputPane.ScrollBars = "Vertical" $outputPane.Font = "Consolas" $outputPane.Dock = "Top" $outputPane.Height = 300 ## Create the root node, which represents the object ## we are trying to show. $root = New-Object Windows.Forms.TreeNode $root.Text = "$InputObject : " + $InputObject.GetType() $root.Name = '$' + $rootVariableName $root.Expand() $null = $treeView.Nodes.Add($root) ## And populate the initial information into the tree ## view. PopulateNode $root $InputObject ## Finally, create the main form and show it. $form = New-Object Windows.Forms.Form $form.Text = "Browsing " + $root.Text $form.Width = 1000 $form.Height = 800 $form.Controls.Add($outputPane) $form.Controls.Add($treeView) $null = $form.ShowDialog() $form.Dispose()