Powershell 请解释此LAN唤醒脚本是如何工作的

几个月前我在博客上发现了这个PowerShell代码。它将LAN唤醒信号发送到您选择的MAC地址，而无需使用外部程序。我在博客上发表了评论，并要求作者描述脚本背后的逻辑，因为我对它很好奇。稍后我又回到了这篇博文，看看作者是否回复了我的评论。我很惊讶地看到，我被重定向到一个页面，作者说他因为崩溃而丢失了他的博客。我记不起它的细节了，但我想我再也没有把那个博客放进书签了

现在我想请Stack Overflow的聪明人看看这段代码，并向我解释它的逻辑。每行加一条评论就太棒了。我很想知道这是怎么回事。它似乎比我发现的其他脚本更健壮，因为它跨子网工作。不过，我对人际网络知之甚少

我最好奇的事情之一是结尾的for循环。为什么要多次发送信号？为什么在不同的港口？但我真的很想知道整个剧本背后的逻辑

守则：

param(
$targetMac，
$network=[net.ipaddress]：：广播，
$subnet=[net.ipaddress]：：广播
)
试一试{
if（$network.gettype（）.equals（[string]））{
$network=[net.ipaddress]：：Parse（$network）；
}
如果（$subnet.gettype（）.equals（[string]））{
$subnet=[net.ipaddress]：：解析（$subnet）；
}
$broadcast=新对象net.ipaddress（（[system.net.ipaddress]：：parse（“255.255.255.255”）.address-bxor$subnet.address-bor$network.address））
$mac=[Net.NetworkInformation.PhysicalAddress]：：Parse（$targetMac.toupper（）.replace（“，”））
$u=新对象net.sockets.udpclient
$ep=新对象net.ipendpoint$broadcast，0
$ep2=新对象net.ipendpoint$broadcast，7
$ep3=新对象net.ipendpoint$broadcast，9
$payload=[byte[]@（255255，255255）；
$payload+=（$mac.GetAddressBytes（）*16）
对于（$i=0；$i-lt 10；$i++）{
$u.Send（$payload，$payload.Length，$ep）|输出空值
$u.Send（$payload，$payload.Length，$ep2）|输出空值
$u.Send（$payload，$payload.Length，$ep3）|输出空值
睡眠1；
}
}抓住{
$Error |写入错误；
}

维基百科对局域网唤醒有很好的解释：

那篇文章的摘录：

[The Magic Packet] is typically sent as a UDP datagram to port 7 or 9, but actually it can be sent on any port. [魔法包]通常作为UDP数据报发送到端口7或9，但实际上它可以是 发送到任何端口。

---

我的猜测之所以多次发送数据包，是因为偶尔会发生网络冲突。如果发生冲突，则必须重新发送数据包。

非常感谢您的帮助！详细阅读Wiki链接：“…然后是目标计算机48位MAC地址的16次重复…”。非常感谢！一、 我也认为没有必要发送十个魔法包。我想知道剧本的作者是否有这样的理由。哦，是这样吗？

#These are the parameters to the script. The only mandatory param here is the mac address
#[net.ipaddress]::Broadcast will resolve to something like 255.255.255.255
param (
    $targetMac,
    $network = [net.ipaddress]::Broadcast,
    $subnet = [net.ipaddress]::Broadcast
)

#We start the try, catch error handling here.
#if something in try block fails, the catch block will write the error
try {

#This will evaludate to False. Hence, $network will have whatever was passed through params or the default value
#in this case the default value is 255.255.255.255
    if($network.gettype().equals([string])) {
        $network = [net.ipaddress]::Parse($network);
    }

#This will evaludate to False. Hence, $network will have whatever was passed through params or the default value
#in this case the default value is 255.255.255.255    
    if($subnet.gettype().equals([string])) {
        $subnet = [net.ipaddress]::Parse($subnet);
    }

    #Not sure if this is really required here. But, assuming that the default value for both $network and $subet is 255.255.255.255,
    #this will result in $broadcast set to 255.255.255.255
    $broadcast = new-object net.ipaddress (([system.net.ipaddress]::parse("255.255.255.255").address -bxor $subnet.address -bor $network.address))

#This again assumes that you had given . as the delimeter in MAC address and removes that from MAC address    
    $mac = [Net.NetworkInformation.PhysicalAddress]::Parse($targetMac.toupper().replace(".",""))

#Create a new object of type net.sockets.udpclient
    $u = New-Object net.sockets.udpclient

#WOL magic packet can be sent on port 0, 7, or 9    
#Create a end point for the broadcast address at port 0    
    $ep = New-Object net.ipendpoint $broadcast, 0

#Create a end point for the broadcast address at port 7    
    $ep2 = New-Object net.ipendpoint $broadcast, 7

#Create a end point for the broadcast address at port 9    
    $ep3 = New-Object net.ipendpoint $broadcast, 9

#Create a payload packet
#First, create a byte array
    $payload = [byte[]]@(255,255,255, 255,255,255);

#add the mac address to the above byte array    
    $payload += ($mac.GetAddressBytes()*16)

#Send 10 magic packets for each port number or end point created above.
#one is more than enough. If everything is congfigured properly
    for($i = 0; $i -lt 10; $i++) {
        $u.Send($payload, $payload.Length, $ep) | Out-Null
        $u.Send($payload, $payload.Length, $ep2) | Out-Null
        $u.Send($payload, $payload.Length, $ep3) | Out-Null
        sleep 1;
    }
} catch {
#catch block catches any error from try block
    $Error | Write-Error;
}