使用相同按钮打开关闭摄像头Javascript

<button id="cameraBtn">打开摄像头</button>
<video id="videoElement" autoplay></video>

// 获取按钮和视频元素
var cameraBtn = document.getElementById('cameraBtn');
var videoElement = document.getElementById('videoElement');
var stream = null;

// 检测浏览器是否支持getUserMedia方法
navigator.getUserMedia = (navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia);

// 按钮点击事件处理函数
function toggleCamera() {
  // 检测摄像头是否已打开
  if (stream) {
    // 关闭摄像头
    stream.getTracks().forEach(track => track.stop());
    stream = null;
    videoElement.srcObject = null;
    cameraBtn.innerHTML = '打开摄像头';
  } else {
    // 打开摄像头
    navigator.getUserMedia({ video: true, audio: false }, function (stream) {
      videoElement.srcObject = stream;
      cameraBtn.innerHTML = '关闭摄像头';
    }, function (error) {
      console.log('打开摄像头失败：', error);
    });
  }
}

// 绑定按钮点击事件
cameraBtn.addEventListener('click', toggleCamera);