尝试如下所示.您根本不需要两个变量:

Try like the following. You don't need two variables at all:

$list = Get-QADUser $userid -includeAllProperties 
if ($list.Count -ge 2)
{
    Write-Host "Please select the appropriate user.<br>"
    Foreach ($a in $list)
    {
        Write-Host "<a href=default.ps1x?UserID=$a.LogonName&domain=$domain>$a.logonname - $a.name</a><br>"
    }  
}