如何从c#启动的powershell脚本块中获取返回值

using System;
using System.Diagnostics;
using System.IO;

class Program
{
    static void Main()
    {
        string script = @"
            # PowerShell脚本块
            $result = 'Hello, World!'
            Write-Output $result
        ";

        // 启动PowerShell进程
        ProcessStartInfo psi = new ProcessStartInfo
        {
            FileName = "powershell.exe",
            Arguments = "-NoProfile -ExecutionPolicy Bypass -Command \"" + script + "\"",
            RedirectStandardOutput = true,
            UseShellExecute = false,
            CreateNoWindow = true
        };

        Process process = new Process
        {
            StartInfo = psi
        };

        process.Start();

        // 读取PowerShell进程的输出
        string output = process.StandardOutput.ReadToEnd();

        process.WaitForExit();

        // 输出结果
        Console.WriteLine("返回值: " + output);
    }
}