Error management in an event handler in a powershell form

Question

Hi guys
I wrote a powershell form using event handler. It ask for a name and a IP adress and other things
In the event handler,
- if the user leave the name blank, I open a message box saying it should not be empty
- if the user enter a wrong ip adress, I open a message box saying it should be like x.x.x.x
If both occurs, it displays 2 message box.
But I would like to display only the first message box of the first error and then exit the handler, to avoid displaying many messages.
How to exit from a handler  and stay in the form  (not like the cancel button handler which close the form with a form.close() statement)
I tried break statement or exit without success
thanks
ML

Answer 1

Hi guys
This is the code I wrote today. I may give also the full code of the interface, but it reach 1300 lines.
$Retry variable lets me control the first error in the interface to display the message box.
It's not finished yet, I need to add something like "formclose" if $Retry is false.
I use semicolons because for me, it's easier to read :-).
I'm sorry I don't understand the explanation in your link.
http://msdn.microsoft.com/en-us/library/system.componentmodel.canceleventargs%28v=vs.110%29.aspx
What would happen if I type
$_.Cancel = $true
instead of $Retry = 1, it will exit immediately from the handler ? I can't try now, I'm came back home
Thanks
ML
function IsIP($value) {
$match = "\b(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}\b"
return $value -match $match
function IsURL([string]$Url)
if($Url -eq $null) {return $false}
else {return $Url -match "^(ht|f)tp(s?)\:\/\/[0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*"+`
"(:(0-9)*)*(\/?)([a-zA-Z0-9\-\.\?\,\'\/\\\+&%\$#_]*)?$"}
function toBinary ($dottedDecimal){
$dottedDecimal.split(".") | %{$binary=$binary + $([convert]::toString($_,2).padleft(8,"0"))}
return $binary
#Provide Custom Code for events specified in PrimalForms.
$handler_WinFactoryGUI_Load=
#TODO: Place custom script here
$HardwareCombo.SelectedIndex = 0 # Default values of Combo boxes
$WindowsEditionCombo.SelectedIndex = 0
$ServerName.Select()
$handler_cancel_Click=
#TODO: Place custom script here
$WinFactoryGUI.Close()
$Handler_Server_Info_Leave=
#TODO: Place custom script here
$Handler_DNS_Config_Leave=
#TODO: Place custom script here
$Handler_GenerateIso_Click=
#TODO: Place custom script here
$Retry = $false
# ServerName
$ServerName2Install = $ServerName.Text
if ($ServerName2Install -eq "") {$MSg = "Server name is missing"; $Retry = $true}
# Windows Version
$TabWindowsVersion = @("2008R2STD","2008R2ENT","2008R2DTC","2012R2STD","2012R2DTC")
$i = $WindowsEditionCombo.SelectedIndex
$WindowsVersion = $TabWindowsVersion[$i]
if (! $Retry) {
# OperIP : mandatory
$OperIP = $OperIP1.Text + "." + $OperIP2.Text + "." + $OperIP3.Text + "." + $OperIP4.Text
$OperMask = $OperMask1.Text + "." + $OperMask2.Text + "." + $OperMask3.Text + "." + $OperMask4.Text
$DefaultGateway = $Gateway1.Text + "." + $Gateway2.Text + "." + $Gateway3.Text + "." + $Gateway4.Text
$Msg = ""
$OperIPOK = IsIP($OperIP); if (! $OperIPOK) { $Msg = $Msg + "OperIP is invalid`n";$Retry = $true }
$OperMaskOK = IsIP($OperMask); if (! $OperMaskOK) { $Msg = $Msg + "OperMask is invalid`n";$Retry = $true }
$DefaultGatewayOK = IsIP($DefaultGateway); if (! $DefaultGatewayOK) { $Msg = $Msg + "DefaultGateway is invalid`n";$Retry = $true}
$ipBinary = toBinary $OperIP
$smBinary = toBinary $OperMask
#how many bits are the network ID
$netBits=$smBinary.indexOf("0")
#validate the subnet mask
if(($smBinary.length -ne 32) -or ($smBinary.substring($netBits).contains("1") -eq $true)) {$Msg = "Subnet Mask is invalid!";$Retry = $true}
else {
#validate that the IP address
if(($ipBinary.length -ne 32) -or ($ipBinary.substring($netBits) -eq "00000000") -or ($ipBinary.substring($netBits) -eq "11111111")) {$Msg = "IP Address is invalid!";$Retry = $True}
# TechIP : optional
if (!$Retry) {
if (($TechIP1.Text -eq "") -and ($TechIP2.Text -eq "") -and ($TechIP3.Text -eq "") -and ($TechIP4.Text -eq ""))
$TechIP = "0.0.0.0"
$TechMask = "0.0.0.0"
else
$TechIP = $TechIP1.Text + "." + $TechIP2.Text + "." + $TechIP3.Text + "." + $TechIP4.Text
$TechMask = $TechMask1.Text + "." + $TechMask2.Text + "." + $TechMask3.Text + "." + $TechMask4.Text
$TechIPOK = IsIP($TechIP)
if (! $TechIPOK) { $Msg = $Msg + "TechIP is invalid`n";$Retry = $true }
$TechMaskOK = IsIP($TechMask)
if (! $TechMaskOK) { $Msg = $Msg + "TechMask is invalid`n";$Retry = $true }
# DNS domain
if (! $Retry) {
$DnsDomainSrv2Install = $DnsDomain.Text
if ($DnsDomainSrv2Install -eq "") {$Msg = $Msg + "DNS Domain is invalid`n";$Retry = $true }
# DNS Suffixes
if (! $Retry) {
$DnsSuffixes2Install = $DnsSuffixes.Text.replace("`n",":")
if ($DnsSuffixes2Install[$DnsSuffixes2Install.Length] -eq ":") {
$DnsSuffixes2Install = $DnsSuffixes2Install.Substring(0,$DnsSuffixes2Install.Length-1)
if ($DnsSuffixes2Install -eq "") {$Msg = $Msg + "DNS suffixes list is invalid`n";$Retry = $true }
# DNS adresses
if (! $Retry) {
if ($DNSIP11.Text -ne "") {
$DNSIP1 = $DNSIP11.Text + "." + $DNSIP12.Text + "." + $DNSIP13.Text + "." + $DNSIP14.Text
$DNSIP1POK = IsIP($DNSIP1) ; if (! $DNSIP1POK) { $Msg = $Msg + "DNS IP 1 is invalid`n";$Retry = $true } else { $DNSAddrList = $DNSIP1}
if ($DNSIP21.Text -ne "") {
$DNSIP2 = $DNSIP21.Text + "." + $DNSIP22.Text + "." + $DNSIP23.Text + "." + $DNSIP24.Text
$DNSIP2POK = IsIP($DNSIP2) ; if (! $DNSIP2POK) { $Msg = $Msg + "DNS IP 2 is invalid`n";$Retry = $true } else {$DNSAddrList = $DNSAddrList + ":" + $DNSIP2}
if ($DNSIP31.Text -ne "") {
$DNSIP3 = $DNSIP31.Text + "." + $DNSIP32.Text + "." + $DNSIP33.Text + "." + $DNSIP34.Text
$DNSIP3POK = IsIP($DNSIP3) ; if (! $DNSIP3POK) { $Msg = $Msg + "DNS IP 3 is invalid`n";$Retry = $true } else {$DNSAddrList = $DNSAddrList + ":" + $DNSIP3}
if ($DNSIP41.Text -ne "") {
$DNSIP4 = $DNSIP41.Text + "." + $DNSIP42.Text + "." + $DNSIP43.Text + "." + $DNSIP44.Text
$DNSIP4POK = IsIP($DNSIP4) ; if (! $DNSIP4POK) { $Msg = $Msg + "DNS IP 4 is invalid`n";$Retry = $true } else {$DNSAddrList = $DNSAddrList + ":" + $DNSIP4}
else { $Msg = $Msg + "At least, one Dns server IP must be provided`n";$Retry = $true }
# Hardware
$TabHardware = @("VM","HP","MS")
$i = $HardwareCombo.SelectedIndex
$Hardware = $TabHardware[$i]
# vCenter
$vCenterName = "parameter.not.used"
# Flags
#""_;_;_;1;_;http://m011ML-SCCM.pocx86.tstwinx.net:8530;1"""
if (! $Retry) {
$Flag = ""
if ($CheckBoxPED.Checked -eq $true) {$Flag = $Flag + "1;"} else {$Flag = $Flag + "_;"}
if ($CheckBoxOmnivision.Checked -eq $true) {$Flag = $Flag + "1;"} else {$Flag = $Flag + "_;"}
if ($CheckBoxBackup.Checked -eq $true) {$Flag = $Flag + "1;"} else {$Flag = $Flag + "_;"}
if ($CheckBoxNagiosInstall.Checked -eq $true) {$Flag = $Flag + "1;"} else {$Flag = $Flag + "_;"}
if ($CheckBoxInstallSRM.Checked -eq $true) {$Flag = $Flag + "1;"} else {$Flag = $Flag + "_;"}
$WsusUrl2Configure = $WsusUrl.Text;
if ($WsusUrl2Configure -eq "") {$WsusUrl2Configure = "_"}
else {
$WsusURLOK = IsUrl($WsusUrl2Configure)
if (! $WsusURLOK) {$Msg = $Msg + "WSUS Url is Invalid`n";$Retry = $true }
$Flag = $Flag + $WsusUrl2Configure
if ($CheckBoxHPSA.Checked -eq $true) {$Flag = $Flag + ";1"} else {$Flag = $Flag + ";_"}
$Flag = """""$Flag"""""""
if ($Retry) {[System.Windows.Forms.MessageBox]::Show($Msg,"Status",0);$Msg = ""}
else { $WinFactoryCall = "start-process ""cmd.exe"" ""/c .\GenBootImage.cmd "
$WinFactoryCall = $WinFactoryCall + $ServerName2Install + " " + $WindowsVersion + " " + $OperIP + " " + $OperMask + " " + $DefaultGateway + " " + $TechIP + " " + $TechMask
$WinFactoryCall = $WinFactoryCall + " " + $DNSAddrList + " " + $DnsDomainSrv2Install + " " + $DnsSuffixes2Install + " " + $Hardware + " " + $vCenterName + " " + $Flag + " -wait"
write-host $WinFactoryCall
$OnLoadForm_StateCorrection=
{#Correct the initial state of the form to prevent the .Net maximized form issue
$WinFactoryGUI.WindowState = $InitialFormWindowState
ML