如何:

if (typeof screen.orientation !== 'undefined') { ... }

.．.因为智能手机通常支持这个属性，而桌面浏览器不支持。在MDN中见。

编辑1:正如@Gajus指出的，窗口。Orientation现在已弃用，不应该使用。

编辑2:您可以使用实验屏幕。Orientation而不是弃用的window.orientation。在MDN中见。

编辑3:从窗口更改。朝向屏幕。朝向

const isMobile = {
    Android: function() {
        return navigator.userAgent.match(/Android/i);
    },
    BlackBerry: function() {
        return navigator.userAgent.match(/BlackBerry/i);
    },
    iOS: function() {
        return navigator.userAgent.match(/iPhone|iPad|iPod/i);
    },
    Opera: function() {
        return navigator.userAgent.match(/Opera Mini/i);
    },
    Windows: function() {
        return navigator.userAgent.match(/IEMobile/i) || navigator.userAgent.match(/WPDesktop/i);
    },
    any: function() {
        return (isMobile.Android() || isMobile.BlackBerry() || isMobile.iOS() || isMobile.Opera() || isMobile.Windows());
    }
};

如何使用

if( isMobile.any() ) alert('Mobile');

要查看用户是否在特定的移动设备上:

if( isMobile.iOS() ) alert('iOS');

裁判:http://www.abeautifulsite.net/blog/2011/11/detecting-mobile-devices-with-javascript

github上的增强版:https://github.com/smali-kazmi/detect-mobile-browser

这是一个比匹配更有效的userAgent解决方案…

function _isMobile(){
    // if we want a more complete list use this: http://detectmobilebrowsers.com/
    // str.test() is more efficent than str.match()
    // remember str.test is case sensitive
    var isMobile = (/iphone|ipod|android|ie|blackberry|fennec/).test
         (navigator.userAgent.toLowerCase());
    return isMobile;
}

  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

请注意，现在大多数新一代移动设备的分辨率都大于600x400。例如，一部iPhone 6....

测试证明: 在这里运行最多赞和最近的帖子，有一个可选的检查，像这样运行:

(function(a){
    window.isMobile = (/(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)))
})(navigator.userAgent||navigator.vendor||window.opera);

alert("This browser was found to be a % browser.", window.isMobile ? 'mobile' : 'desktop');

不知何故，在以下浏览器应用程序上返回了以下结果。配置:iPhone 6S, iOS 10.3.1。

Safari(最新):将其作为移动设备检测。

Chrome(最新):没有检测到它作为一个移动。

SO, i then tested the suggestion from Lanti (https://stackoverflow.com/a/31864119/7183483), and it did return the proper results (mobile for all iOS devices, and desktop for my Mac). Therefore, i proceeded to edit it a little since it would fire twice (for both mobile and Tablet). I then noticed when testing on an iPad, that it also returned as a mobile, which makes sense, since the Parameters that Lanti uses check the OS more than anything. Therefore, i simply moved the tablet IF statement inside the mobile check, which would return mobile is the Tablet check was negative, and tablet otherwise. I then added the else clause for the mobile check to return as desktop/laptop, since both qualify, but then noticed that the browser detects CPU and OS brand. So i added what is returned in there as part of else if statement instead. To cap it, I added a cautionary else statement in case nothing was detected. See bellow, will update with a test on a Windows 10 PC soon.

哦，我还添加了一个'debugMode'变量，以便在调试和正常编译之间轻松切换。

Dislaimer:这完全是Lanti的功劳，而且这款游戏没有在Windows平板电脑上测试……它可能会返回桌面/笔记本电脑，因为操作系统是纯Windows。等我找到用手机的朋友我会查的。

function userAgentDetect() {
    let debugMode = true;
    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)) {
        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)) {
            window.deviceTypeVar = 'tablet';
            if (debugMode === true) {
                alert('Device is a tablet - ' + navigator.userAgent);
            }
        } else {
            if (debugMode === true) {
                alert('Device is a smartphone - ' + navigator.userAgent);
            };
            window.deviceTypeVar = 'smartphone';
        }
    } else if (window.navigator.userAgent.match(/Intel Mac/i)) {
        if (debugMode === true) {
            alert('Device is a desktop or laptop- ' + navigator.userAgent);
        }
        window.deviceTypeVar = 'desktop_or_laptop';
    } else if (window.navigator.userAgent.match(/Nexus 7/i)
        || window.navigator.userAgent.match(/Nexus 10/i)
        || window.navigator.userAgent.match(/KFAPWI/i)) {
        window.deviceTypeVar = 'tablet';
        if (debugMode === true) {
            alert('Device is a tablet - ' + navigator.userAgent);
        }
    } else {
        if (debugMode === true) {
            alert('Device is unknown- ' + navigator.userAgent);
        }
        window.deviceTypeVar = 'Unknown';
    }
}

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;
}