如何在PowerShell中自动执行Write-Host生成的GAMADV-XTD3命令？

我正在使用GAMADV-XTD3命令行工具，在Google Workspace中自动化处理邮箱签名、云端硬盘权限等事务。近期需要为员工设置外出自动回复，编写了PowerShell脚本用于输入用户邮箱、休假起止日期，生成对应的GAM命令字符串，但目前只能手动复制粘贴执行。请问如何实现命令的自动执行？

当前使用的脚本如下：

$email = Read-Host -Prompt "enter email"
$startdate = Read-Host -Prompt "enter startdate"
$enddate = Read-Host -Prompt "enter enddate" 
Write-Host "gam user $email vacation on subject "`"Out of Office from 
$startdate - $enddate`"" message "`"Out of the office from $startdate 
to $enddate. If there are any issues or emergencies that you need 
addressed in my absence please contact my manager `"" html startdate 
$startdate enddate $enddate"

不需要通过Write-Host输出命令再手动执行，直接在PowerShell中调用GAM命令即可，PowerShell会自动完成变量替换和参数传递：

方法一：直接调用GAM命令（推荐） #

这种方式避免了字符串转义的麻烦，也更安全（无命令注入风险）：

$email = Read-Host -Prompt "enter email"
$startdate = Read-Host -Prompt "enter startdate"
$enddate = Read-Host -Prompt "enter enddate"

# 直接执行GAM命令，无需生成字符串
gam user $email vacation on `
  subject "Out of Office from $startdate - $enddate" `
  message "Out of the office from $startdate to $enddate. If there are any issues or emergencies that you need addressed in my absence please contact my manager" `
  html `
  startdate $startdate `
  enddate $enddate

方法二：构造命令字符串后执行（不推荐） #

如果因特殊需求必须先生成命令字符串，可使用Invoke-Expression执行，但需注意变量内容的安全性：

$email = Read-Host -Prompt "enter email"
$startdate = Read-Host -Prompt "enter startdate"
$enddate = Read-Host -Prompt "enter enddate"

# 构造命令字符串（注意双引号的转义）
$gamCommand = "gam user $email vacation on subject `"Out of Office from $startdate - $enddate`" message `"Out of the office from $startdate to $enddate. If there are any issues or emergencies that you need addressed in my absence please contact my manager`" html startdate $startdate enddate $enddate"

# 执行命令字符串
Invoke-Expression $gamCommand

内容的提问来源于stack exchange，提问作者Latif Bouzoubaa