这取决于用例。所有的移动设备都需要电池。如果你想要的是在不耗尽电池的情况下计算电量，使用电池状态API:

navigator.getBattery().then(battery => {
  battery.charging ? 'charging' : 'not charging';
});

如果您正在寻找的是表示的使用matchMedia，它返回一个布尔值:

if (window.matchMedia("(min-width: 400px)").matches) {
  /* the viewport is at least 400 pixels wide */
} else {
  /* the viewport is less than 400 pixels wide */
}

或者将它们结合起来，在平板设备上获得更好的用户体验。

这也是一种解决方案。

var isMobile = false; //initiate as false

  // device detection
  if(/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|ipad|iris|kindle|Android|Silk|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i.test(navigator.userAgent) 
  || /1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(navigator.userAgent.substr(0,4))) isMobile = true;

  console.log('Mobile device:'+isMobile);

  var doc_h = $(document).height(); // returns height of HTML document
  var doc_w = $(document).width(); // returns width of HTML document
  console.log('Height: '+doc_h);
  console.log('width: '+doc_w);

  var iPadVertical = window.matchMedia("(width: 768px) and (height: 1024px) and (orientation: portrait)");
  var iPadHoricontal = window.matchMedia("(width: 1024px) and (height: 767px) and (orientation: landscape)");

  console.log('Height: '+doc_h);
  console.log('width: '+doc_w);

  if (iPadVertical.matches) {
      console.log('Ipad vertical detected');
  }else if (iPadHoricontal.matches){
      console.log('Ipad horicontal detected');
  }else {
      console.log('No Ipad');
  }

如果你使用这两种方法，你将得到一个完美的方法来检测不同的设备。

这取决于用例。所有的移动设备都需要电池。如果你想要的是在不耗尽电池的情况下计算电量，使用电池状态API:

navigator.getBattery().then(battery => {
  battery.charging ? 'charging' : 'not charging';
});

如果您正在寻找的是表示的使用matchMedia，它返回一个布尔值:

if (window.matchMedia("(min-width: 400px)").matches) {
  /* the viewport is at least 400 pixels wide */
} else {
  /* the viewport is less than 400 pixels wide */
}

或者将它们结合起来，在平板设备上获得更好的用户体验。

没有完美的解决方案来检测JS代码是否在移动浏览器上执行，但以下两个选项应该在大多数情况下都有效。

选项1:浏览器嗅探

!function(a){var b=/iPhone/i,c=/iPod/i,d=/iPad/i,e=/(?=.*\bAndroid\b)(?=.*\bMobile\b)/i,f=/Android/i,g=/(?=.*\bAndroid\b)(?=.*\bSD4930UR\b)/i,h=/(?=.*\bAndroid\b)(?=.*\b(?:KFOT|KFTT|KFJWI|KFJWA|KFSOWI|KFTHWI|KFTHWA|KFAPWI|KFAPWA|KFARWI|KFASWI|KFSAWI|KFSAWA)\b)/i,i=/IEMobile/i,j=/(?=.*\bWindows\b)(?=.*\bARM\b)/i,k=/BlackBerry/i,l=/BB10/i,m=/Opera Mini/i,n=/(CriOS|Chrome)(?=.*\bMobile\b)/i,o=/(?=.*\bFirefox\b)(?=.*\bMobile\b)/i,p=new RegExp("(?:Nexus 7|BNTV250|Kindle Fire|Silk|GT-P1000)","i"),q=function(a,b){return a.test(b)},r=function(a){var r=a||navigator.userAgent,s=r.split("[FBAN");return"undefined"!=typeof s[1]&&(r=s[0]),s=r.split("Twitter"),"undefined"!=typeof s[1]&&(r=s[0]),this.apple={phone:q(b,r),ipod:q(c,r),tablet:!q(b,r)&&q(d,r),device:q(b,r)||q(c,r)||q(d,r)},this.amazon={phone:q(g,r),tablet:!q(g,r)&&q(h,r),device:q(g,r)||q(h,r)},this.android={phone:q(g,r)||q(e,r),tablet:!q(g,r)&&!q(e,r)&&(q(h,r)||q(f,r)),device:q(g,r)||q(h,r)||q(e,r)||q(f,r)},this.windows={phone:q(i,r),tablet:q(j,r),device:q(i,r)||q(j,r)},this.other={blackberry:q(k,r),blackberry10:q(l,r),opera:q(m,r),firefox:q(o,r),chrome:q(n,r),device:q(k,r)||q(l,r)||q(m,r)||q(o,r)||q(n,r)},this.seven_inch=q(p,r),this.any=this.apple.device||this.android.device||this.windows.device||this.other.device||this.seven_inch,this.phone=this.apple.phone||this.android.phone||this.windows.phone,this.tablet=this.apple.tablet||this.android.tablet||this.windows.tablet,"undefined"==typeof window?this:void 0},s=function(){var a=new r;return a.Class=r,a};"undefined"!=typeof module&&module.exports&&"undefined"==typeof window?module.exports=r:"undefined"!=typeof module&&module.exports&&"undefined"!=typeof window?module.exports=s():"function"==typeof define&&define.amd?define("isMobile",[],a.isMobile=s()):a.isMobile=s()}(this); alert(isMobile.any ? 'Mobile' : 'Not mobile');

这个特殊的浏览器嗅探代码是一个名为isMobile的库的代码。

选项2:window.orientation

测试如果窗口。定义方向:

var isMobile = window.orientation > -1; alert（isMobile ？“移动设备”：“非移动设备”）;

Note

并不是所有的触屏设备都是移动的，反之亦然。所以，如果你想实现一些专门针对触摸屏的东西，你不应该测试你的浏览器是否在移动设备上运行，而应该测试设备是否支持触摸屏:

var hasTouchscreen = 'ontouchstart'在窗口; 警报(hasTouchscreen ?'有触摸屏':'没有触摸屏');

使用Regex:

/* eslint-disable */
export const IS_MOBILE = (function (a) {
  return (
    /(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i
      .test(
        a.substr(0,4)
      )
  )
  // @ts-ignore
})(navigator.userAgent || navigator.vendor || window.opera)
/* eslint-enable */

正如许多人所说，依赖于用户代理数据的移动目标是有问题的。这同样适用于屏幕大小的计数。

我的方法借鉴了CSS技术来确定界面是否是触摸的:

只使用javascript(所有现代浏览器都支持)，媒体查询匹配可以轻松推断设备是否是移动设备。

function isMobile() {
    var match = window.matchMedia || window.msMatchMedia;
    if(match) {
        var mq = match("(pointer:coarse)");
        return mq.matches;
    }
    return false;
}