常用技巧

媒体设备

下面是获取设备列表与调用摄像头的示例

//获取设备列表
navigator.mediaDevices.enumerateDevices().then((devices) => {
  devices.forEach(function (device) {
      console.log(device.kind + ': ' + device.label + ' id = ' + device.deviceId)
  })
})
//定义设备参数，deviceId 是通过 navigator.mediaDevices.enumerateDevices 获取到的
var constraints = {
  audio: false,
  video: { width: 1920, height: 1080, deviceId: '3ac2c7ced105773790f6ce126b7a90453b66c2d5f4a63852e6990d2bcd196792' },
}

//调用摄像头
navigator.mediaDevices
.getUserMedia(constraints)
.then(function (mediaStream) {
    var video = document.querySelector('video')
    video.srcObject = mediaStream
    video.onloadedmetadata = function (e) {
        video.play()
    }
}).catch(function (err) {
    console.log(err.name + ': ' + err.message)
})