这里是一个ECMAScript 6解决方案(TypeScript就绪)

public isMobile(): boolean {
  let check = false;
  ((a => {
      if (/(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))) check = true;
      }))(navigator.userAgent || navigator.vendor);
  return check;
 }

像这样的怎么样?

if(
    (screen.width <= 640) || 
    (window.matchMedia && 
     window.matchMedia('only screen and (max-width: 640px)').matches
    )
  ){
   // Do the mobile thing
}

使用Regex:

这里有一个函数，它使用了一个疯狂的长而全面的正则表达式，根据用户是否使用手机浏览，返回一个true或false值。

window.mobileCheck = function() {
  let check = false;
  (function(a){if(/(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))) check = true;})(navigator.userAgent||navigator.vendor||window.opera);
  return check;
};

对于那些希望在这个测试中包含平板电脑的人(尽管有争议，你不应该)，你可以使用以下函数:

window.mobileAndTabletCheck = function() {
  let check = false;
  (function(a){if(/(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|android|ipad|playbook|silk/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))) check = true;})(navigator.userAgent||navigator.vendor||window.opera);
  return check;
};

使用navigator.userAgentData

你也可以使用navigator.userAgentData。但是userAgentData仍然是实验性的，所以不建议在生产中使用。

const isMobile = navigator.userAgentData.mobile; //resolves true/false

userAgentData的兼容性图

最初的答案

你可以通过简单地运行一个设备列表并检查useragent是否匹配如下所示:

  function detectMob() {
    const toMatch = [
        /Android/i,
        /webOS/i,
        /iPhone/i,
        /iPad/i,
        /iPod/i,
        /BlackBerry/i,
        /Windows Phone/i
    ];
    
    return toMatch.some((toMatchItem) => {
        return navigator.userAgent.match(toMatchItem);
    });
}

然而，既然你认为这种方法不可靠，你可以假设任何分辨率为800x600或更低的设备也是移动设备，从而进一步缩小你的目标(尽管现在许多移动设备的分辨率比这个高得多)。

i.e

  function detectMob() {
    return ( ( window.innerWidth <= 800 ) && ( window.innerHeight <= 600 ) );
  }

参考:

用javascript检测浏览器和设备

  isMobile() {
    if ('maxTouchPoints' in navigator) return navigator.maxTouchPoints > 0;

    const mQ = matchMedia?.('(pointer:coarse)');
    if (mQ?.media === '(pointer:coarse)') return !!mQ.matches;
    
    if ('orientation' in window) return true;
    
    return /\b(BlackBerry|webOS|iPhone|IEMobile)\b/i.test(navigator.userAgent) ||
      /\b(Android|Windows Phone|iPad|iPod)\b/i.test(navigator.userAgent);
  }

导航器。不建议使用userAgent嗅探，因为它不可靠且变化很大。正如您在这里看到的:https://developers.whatismybrowser.com/useragents/explore/导航器。userAgent字符串在同一浏览器的不同版本之间可能有很大差异。

这篇MDN文章可以支持这种说法:https://developer.mozilla.org/en-US/docs/Web/HTTP/Browser_detection_using_the_user_agent#avoiding_user_agent_detection。

上面的答案是对著名的MDN文章中建议的移动检测解决方案的重构。它首先依赖于特性检查，然后作为导航器的最后手段进行回退。userAgent嗅探。

编码快乐!＜3

我还没看到有人建议:

window.navigator.connection.type

这只存在于移动设备上，不存在于桌面浏览器上。检查该属性是否存在更简单，即if(window && window。Navigator && window.navigator.connection && window.navigator.connection.type) =>那么它是移动的

注意:这是实验性的

EDIT(07.2022):该功能被认为是一个潜在的跟踪漏洞，因此将从最新版本中删除。换句话说，不要用这个!

以下是我对这个问题的重新思考的解决方案。仍然不完美。唯一真正的解决方案是设备制造商开始认真对待“移动”和“平板”用户代理字符串。

window.onload = userAgentDetect;
function userAgentDetect() {
  if(window.navigator.userAgent.match(/Mobile/i)
  || window.navigator.userAgent.match(/iPhone/i)
  || window.navigator.userAgent.match(/iPod/i)
  || window.navigator.userAgent.match(/IEMobile/i)
  || window.navigator.userAgent.match(/Windows Phone/i)
  || window.navigator.userAgent.match(/Android/i)
  || window.navigator.userAgent.match(/BlackBerry/i)
  || window.navigator.userAgent.match(/webOS/i)) {
    document.body.className += ' mobile';
    alert('True - Mobile - ' + navigator.userAgent);
  } else {
    alert('False - Mobile - ' + navigator.userAgent);
  }
  if(window.navigator.userAgent.match(/Tablet/i)
  || window.navigator.userAgent.match(/iPad/i)
  || window.navigator.userAgent.match(/Nexus 7/i)
  || window.navigator.userAgent.match(/Nexus 10/i)
  || window.navigator.userAgent.match(/KFAPWI/i)) {
    document.body.className -= ' mobile';
    document.body.className += ' tablet';
    alert('True - Tablet - ' + navigator.userAgent);
  } else {
    alert('False - Tablet - ' + navigator.userAgent);
  }
}

当Nexus 7平板电脑只有Android UA字符串时会发生什么?首先，Mobile变成true，之后Tablet也变成true，但是Tablet会从body标签中删除Mobile UA字符串。

CSS:

body.tablet { background-color: green; }
body.mobile { background-color: red; }

为开发添加了警报线。Chrome控制台可以模拟许多手持设备。测试。

编辑:

不要使用这种方法，而是使用特征检测。市场上有如此多的设备和品牌，瞄准一个品牌永远不是正确的解决方案。