Release-DHCPLease.ps1

    Param(
    [Parameter(Mandatory=$true,Position=0)] $ImportModuleFrom,
    [Parameter(Position=1)] $LogPath
     )

Function Create-Form
{
    [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")  | Out-Null

    # Create the Conatainer Form  to place the Labels and Textboxes
    $Form = New-Object “System.Windows.Forms.Form”;
    $Form.Width = 350;
    $Form.Height = 200;
    $Form.Text = 'Enter the required details'
    $Form.StartPosition = [System.Windows.Forms.FormStartPosition]::CenterScreen;
    $Form.TopMost = $true

    #Define Label1
    $Label1 = New-Object “System.Windows.Forms.Label”;
    $Label1.Left = 10;
    $Label1.Top = 15;
    $Label1.Text = 'Server Name';
    #Define Label2
    $Label2 = New-Object “System.Windows.Forms.Label”;
    $Label2.Left = 10;
    $Label2.Top = 50;
    $Label2.Text = 'Scope ID';
    #Define Label3
    $Label3 = New-Object “System.Windows.Forms.Label”;
    $Label3.Left = 10;
    $Label3.Top = 85;
    $Label3.Width = 180
    $Label3.Text = 'No. of IP Lease to be removed ?';

    #Define TextBox1 for input
    $TextBox1 = New-Object “System.Windows.Forms.TextBox”;
    $TextBox1.Left = 200;
    $TextBox1.Top = 10;
    $TextBox1.width = 100;
    #Define TextBox2 for input
    $TextBox2 = New-Object “System.Windows.Forms.TextBox”;
    $TextBox2.Left = 200;
    $TextBox2.Top = 50;
    $TextBox2.width = 100;
    #Define TextBox3 for input
    $TextBox3 = New-Object “System.Windows.Forms.TextBox”;
    $TextBox3.Left = 200;
    $TextBox3.Top = 85;
    $TextBox3.width = 100;

    #Define OK Button
    $OKbutton = New-Object “System.Windows.Forms.Button”;
    $OKbutton.Left = 20;
    $OKbutton.Top = 120;
    $OKbutton.Width = 100;
    $OKbutton.Text = “OK”;



    ############# This is when you have to close the Form after getting values
    $eventHandler = [System.EventHandler]{
    $TextBox1.Text;
    $TextBox2.Text;
    $TextBox3.Text;
    $Form.Close();};

    $OKbutton.Add_Click($eventHandler) ;

    #Add controls to the Form
    $Form.Controls.Add($OKbutton);
    $Form.Controls.Add($Label1);
    $Form.Controls.Add($Label2);
    $Form.Controls.Add($Label3);
    $Form.Controls.Add($TextBox1);
    $Form.Controls.Add($TextBox2);
    $Form.Controls.Add($TextBox3);
    $Form.ShowDialog()|Out-Null

    Return $TextBox1.Text,$TextBox2.Text,$TextBox3.Text


}

Function Remove-DHCPLease($Server, $ScopeID, $Count)
{

$Start = Get-Date

    [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") | Out-Null

    # Create the Conatainer Form  to place the Labels and Textboxes
    $Form = New-Object “System.Windows.Forms.Form”;
    $Form.Text = 'Collecting Target IP Addresses'
    $Form.StartPosition = [System.Windows.Forms.FormStartPosition]::CenterScreen;
    $Form.AutoSize = $true
    $Form.TopMost = $true

    #Define Label1
    $Label1 = New-Object “System.Windows.Forms.Label”;
    $Label1.Left = 20;
    $Label1.Top = 20;
    $Label1.AutoSize = $true
    $Label1.Text = "Searching first $count IP Address(es) that are not responding to PING Requests`n`nScope : $ScopeID `nServer : $($server.ToUpper()) `n`nPlease wait for a while, this could take few minutes"
    
    #Define OK Button
    $OKbutton = New-Object “System.Windows.Forms.Button”;
    $OKbutton.Left = 20;
    $OKbutton.Top = $Form.Height - 50
    $OKbutton.Width = 100;
    $OKbutton.Text = “OK”;
    $OKbutton.Enabled = $false

    #Define Cancel Button
    $Cancelbutton = New-Object “System.Windows.Forms.Button”;
    $Cancelbutton.Left = 250;
    $Cancelbutton.Top = $Form.Height - 50
    $Cancelbutton.Width = 100;
    $Cancelbutton.Text = “Cancel”;
        
    $OKbutton.Add_Click(
    {
        #$Form.Controls.Remove($OKbutton)
        $OKbutton.Enabled = $false
        $Label1.text = "Releasing IP Addresses from the scope now ... Please wait."
            
            $TargetIPAddr | Remove-DhcpServerv4Lease -ComputerName $server -ErrorVariable +err
            if($?)
            {
                
                if($LogPath)
                {

                        If($LogPath[-1] -ne '\')
                        {
                            $LogPath = "$LogPath\DCHP_Release_Logs.txt"
                        }
                        else
                        {
                            $LogPath = $LogPath+"DCHP_Release_Logs.txt"
                        }
                }
                else
                {
                    $LogPath = "$((Get-Location).path)\DCHP_Release_Logs.txt"
                }

                "`n**[$((Get-Date).datetime)] Following IP Address(es) were released by USER : $env:USERDOMAIN\$env:USERNAME`n $($TargetIPAddr | %{"`n$($_.hostname) - $($_.IPaddress)"})" -replace "`n", "`r`n"  | set-Content $LogPath
                $PercentUsed = Get-DhcpServerv4ScopeStatistics -ScopeId $ScopeID -ComputerName $server | select PercentageInUse -Expand PercentageInuse

                $Label1.text = "IP Addresses successfully released from the scope and is $(100 - [Int]$PercentUsed)% Free. You can close this window now`n`n`n`nA Log file has been genrated on below path to record this DHCP IP address release(s)`n`n$LogPath"
            }
            Else
            {
                $Label1.text = "Something went wrong. Please close this Window and run the script again. `n $err" 
            }
    }
    )

    $CancelButton.add_click(
    {
        $Form.Close()
    }
    )
    
    #Add controls to the Form
    $Form.Controls.Add($Label1)
    $Form.Controls.Add($OKbutton)
    $Form.COntrols.Add($CancelButton)
    $form.Visible = $true

    $TargetIPAddr = Get-DhcpServerv4lease -computer $server -ScopeId $ScopeID |?{$_.addressstate -notlike '*reservation*' -and $(test-Connection $_.ipaddress -count 4 -Quiet) -eq $false} | select -First $Count
    
    $Finish = Get-Date
    $TimeTaken = $Finish - $Start

    $Form.Visible = $false
    
    $OKbutton.Enabled = $true
    $Form.Text = 'Target IP Addresses'
    $Label1.Text = "`nTIME TAKEN : $($TimeTaken.Minutes) Mins and $($TimeTaken.Seconds) Secs`n"+ $($TargetIPAddr| %{"`n$($_.hostname) - $($_.IPaddress)"})+"`n`nPlease Confirm if you want to delete these IP from  SCOPE : $scopeID on SERVER: $($server.ToUpper()) ?`n`nPress OK to Continue"
   
    $Form.ShowDialog() | Out-Null
}

Import-Module -PSSession (New-PSSession -ComputerName $ImportModuleFrom -Credential (Get-Credential 'Domain\Username')) -Name dhcpserver

$Server,$ScopeID,$Count = Create-Form

$Start = (Get-Date).ToShortTimeString()

Remove-DHCPLease $Server $ScopeID $Count

Get-PSSession | Remove-PSSession