将您的引号引起来，即:

Swap your quotes around, i.e.:

$link = "<a href='http://tsturl/detail.aspx?reqID=$reqID'>$ReqID</a>"

或者这样做:

$link = '<a href="http://tsturl/detail.aspx?reqID=$reqID">$ReqID</a>'
$link = $ExecutionContext.InvokeCommand.ExpandString($link)

在您的评论之外，如果您希望邮件正文呈现为HTML，从而显示一个链接，那么您需要告诉您的邮件客户端该正文是HTML. $ link 只是一个普通的旧字符串，并且不知道它是HTML.

Further to your comment, if you want the mail body to render as HTML, an thus display a link, then you'll need to tell your mail client that the body is HTML. $link is just a plain old string and doesn't know that it's HTML.

从您的上一个问题中，我猜你是重新使用 Send-MailMessage cmdlet.如果是这样，则需要指定 -BodyAsHtml 开关.

From your previous question, I'm guessing you're using the Send-MailMessage cmdlet. If so then you need to specify the -BodyAsHtml switch.