PowerShell In GUI Blog

As can be clearly seen from the survey Ravikanth conducted here http://www.ravichaganti.com/blog/?p=2111 , the great majority of powershellers do write GUI. Moreover, there is no common universal tool. Every powersheller chooses the way one creates user interface.

Well, why don’t we create a small example by using just bare hands. Let’s do our preparation. A recipe is simple: a bit of text editor (Intellisense-enabled is preferable), a piece of rich text or even a text file, and a keyboard.

Supposedly, we need a form with a menu (two-level one, not to be considered as a simpleton), a label and a textbox. The user should be able to manage content of textbox using menu.

There is two ways to create a form:

1.1 by using PrimalForms:

#Generated Form Function
function GenerateForm { 
########################################################################
 # Code Generated By: SAPIEN Technologies PrimalForms (Community Edition) v1.0.10.0
 # Generated On: 26/04/2011 09:43 p.m.
 # Generated By: apetrovskiy
 ########################################################################

#region Import the Assemblies 
[reflection.assembly]::loadwithpartialname("System.Windows.Forms") | Out-Null
[reflection.assembly]::loadwithpartialname("System.Drawing") | Out-Null
#endregion
#region Generated Form Objects 
$form1=New-Object System.Windows.Forms.Form
$textBox1=New-Object System.Windows.Forms.TextBox
$label1=New-Object System.Windows.Forms.Label
$InitialFormWindowState=New-Object System.Windows.Forms.FormWindowState
#endregion Generated Form Objects 
#region Generated Form Code 
$System_Drawing_Size=New-Object System.Drawing.Size
$System_Drawing_Size.Height =262
$System_Drawing_Size.Width =284
$form1.ClientSize=$System_Drawing_Size
$form1.DataBindings.DefaultDataSourceUpdateMode=0
$form1.Name="form1"
$form1.Text="Primal Form"
$textBox1.DataBindings.DefaultDataSourceUpdateMode=0
$System_Drawing_Point=New-Object System.Drawing.Point
$System_Drawing_Point.X =34
$System_Drawing_Point.Y =82
$textBox1.Location=$System_Drawing_Point
$textBox1.Name="textBox1"
$System_Drawing_Size=New-Object System.Drawing.Size
$System_Drawing_Size.Height =20
$System_Drawing_Size.Width =195
$textBox1.Size=$System_Drawing_Size
$textBox1.TabIndex=1
$form1.Controls.Add($textBox1) 
$label1.DataBindings.DefaultDataSourceUpdateMode=0
$System_Drawing_Point=New-Object System.Drawing.Point
$System_Drawing_Point.X =36
$System_Drawing_Point.Y =45
$label1.Location=$System_Drawing_Point
$label1.Name="label1"
$System_Drawing_Size=New-Object System.Drawing.Size
$System_Drawing_Size.Height =22
$System_Drawing_Size.Width =177
$label1.Size=$System_Drawing_Size
$label1.TabIndex=0
$label1.Text="label1"
$form1.Controls.Add($label1) 
#endregion Generated Form Code 
#Save the initial state of the form
$InitialFormWindowState=$form1.WindowState
#Init the OnLoad event to correct the initial state of the form
$form1.add_Load($OnLoadForm_StateCorrection) 
#Show the Form
$form1.ShowDialog() | Out-Null } 
#End Function
#Call the Function
GenerateForm

1.2 by typing the following code:

[System.Windows.Forms.Form]$form1=`
New-Object System.Windows.Forms.Form; 
[System.Windows.Forms.Label]$label1=`
New-Object System.Windows.Forms.Label; 
$label1.Name="label1"; 
$label1.Text="label1"; 
$label1.Left=20; 
$label1.Top=50; 
[System.Windows.Forms.TextBox]$textbox1=`
New-Object System.Windows.Forms.TextBox; 
$textbox1.Name="textbox1"; 
$textbox1.Left=20; 
$textbox1.Top=100; 
$form1.Name="form1"; 
$form1.Controls.Add($label1); 
$form1.Controls.Add($textbox1); 
$form1.ShowDialog() | Out-Null;

All our further actions are insertions to be written above the string  $form1.ShowDialog()

2. Now we add the following simple function:

function addMenuItem 
{ 
param([ref]$ParentItem, 
[string]$ItemName='', 
[string]$ItemText='', 
[scriptblock]$ScriptBlock=$null 
) 
[System.Windows.Forms.ToolStripMenuItem]$private:menuItem=`
New-Object System.Windows.Forms.ToolStripMenuItem; 
$private:menuItem.Name =$ItemName; 
$private:menuItem.Text =$ItemText; 
if ($ScriptBlock -ne $null) 
{ $private:menuItem.add_Click(([System.EventHandler]$handler=`
$ScriptBlock)); } 
if (($ParentItem.Value) -is [System.Windows.Forms.MenuStrip]) 
{ ($ParentItem.Value).Items.Add($private:menuItem); } 
if (($ParentItem.Value) -is [System.Windows.Forms.ToolStripItem]) 
{ ($ParentItem.Value).DropDownItems.Add($private:menuItem); } 
return $private:menuItem; 
}

The function receives a reference to the parent menu item, the name and the label chosen for a new menu element, and, if nesessary, scriptblock. Don’t pass a scriptblock to menuitems that are not at the lowest leel of your menu hierarhy.

3. After that it’s time to add a MenuStrip:

[System.Windows.Forms.MenuStrip]$mainMenu=New-Object System.Windows.Forms.MenuStrip; 
$form1.Controls.Add($mainMenu);

If we run our form now, we can see a hardly visible (depending on your color schema) strip at the top of the $form1.

4. Now we can add handlers form menu items. To simplify the example, our handlers are scriptblocks. I wrote one, crischening it as $sb1. Undoubtedly, by searching for $mainMenu in ObjectBrowser untidy code you may find more examples.

[scriptblock]$sb1= { 
#your code
}

5. Finally, we add menu items (see sample code for more details):

#region File 
(addMenuItem -ParentItem ([ref]$mainMenu) -ItemName 'mnuFile' -ItemText 'File' -ScriptBlock $null) | %{ 
$null=addMenuItem -ParentItem ([ref]$_) -ItemName 'mnuFileOpen' -ItemText 'Open' -ScriptBlock $sb1; 
$null=addMenuItem -ParentItem ([ref]$_) -ItemName 'mnuFileSave' -ItemText 'Save' -ScriptBlock $null; 
$null=addMenuItem -ParentItem ([ref]$_) -ItemName 'mnuFileExit' -ItemText 'Exit' -ScriptBlock $null;} | Out-Null; 
#endregion File

Today’s code attached here.