帮我写代码实现unity app启动时录制app画面，app关闭时保存录制的视频

好的，我可以帮你写代码实现这个功能。你需要在Unity中使用Unity Recorder插件来录制应用程序的屏幕，并将录制的视频保存到指定的文件中。以下是其中一种实现方法的示例代码：

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Rendering;

public class ScreenRecorder : MonoBehaviour
{
    public bool isRecording;
    public int videoWidth;
    public int videoHeight;
    public int frameRate;
    public string outputFile;

    private Recorder recorder;

    // Start is called before the first frame update
    void Start()
    {
        gameObject.AddComponent<Camera>();
        var cam = GetComponent<Camera>();
        cam.targetTexture = new RenderTexture(videoWidth, videoHeight, 24);
        cam.enabled = false;

        recorder = gameObject.AddComponent<Recorder>();
        recorder.m_OutputFileName = outputFile;
        recorder.m_ForceAlphaInMJPEG = true;
        recorder.m_Source = RecorderSource.MainCamera;
        recorder.m_FPS = frameRate;

        isRecording = false;
    }

    // Update is called once per frame
    void Update()
    {
        if (Input.GetKeyDown(KeyCode.R))
        {
            if (!isRecording)
            {
                isRecording = true;
                StartRecording();
            }
        }

        if (Input.GetKeyDown(KeyCode.S))
        {
            if (isRecording)
            {
                isRecording = false;
                StopRecording();
            }
        }
    }

    void StartRecording()
    {
        recorder.BeginRecording();
        GetComponent<Camera>().enabled = true;
    }

    void StopRecording()
    {
        GetComponent<Camera>().enabled = false;
        recorder.EndRecording();
    }
}

这个脚本可以附加到启动时的场景中，然后在 Unity 编辑器中设置视频的宽度、高度、帧速率以及保存文件的路径。你可以使用普通的播放器（如Windows Media Player或Quicktime Player）来播放录制的视频文件。