方法1

• designWidth:設(shè)計(jì)稿的實(shí)際寬度值，需要根據(jù)實(shí)際設(shè)置
• maxWidth:制作稿的最大寬度值，需要根據(jù)實(shí)際設(shè)置
• 這段js的最后面有兩個(gè)參數(shù)記得要設(shè)置，一個(gè)為設(shè)計(jì)稿實(shí)際寬度，一個(gè)為制作稿最大寬度，例如設(shè)計(jì)稿為750，最大寬度為750，則為(750,750)

;(function(designWidth, maxWidth) {
  var doc = document,
    win = window,
    docEl = doc.documentElement,
    remStyle = document.createElement("style"),
    tid;

  function refreshRem() {
    var width = docEl.getBoundingClientRect().width;
    maxWidth = maxWidth || 540;
    width>maxWidth && (width=maxWidth);
    var rem = width * 100 / designWidth;
    remStyle.innerHTML = 'html{font-size:' + rem + 'px;}';
  }

  if (docEl.firstElementChild) {
    docEl.firstElementChild.appendChild(remStyle);
  } else {
    var wrap = doc.createElement("div");
    wrap.appendChild(remStyle);
    doc.write(wrap.innerHTML);
    wrap = null;
  }
  //要等 wiewport 設(shè)置好后才能執(zhí)行 refreshRem，不然 refreshRem 會(huì)執(zhí)行2次；
  refreshRem();

  win.addEventListener("resize", function() {
    clearTimeout(tid); //防止執(zhí)行兩次
    tid = setTimeout(refreshRem, 300);
  }, false);

  win.addEventListener("pageshow", function(e) {
    if (e.persisted) { // 瀏覽器后退的時(shí)候重新計(jì)算
      clearTimeout(tid);
      tid = setTimeout(refreshRem, 300);
    }
  }, false);

  if (doc.readyState === "complete") {
    doc.body.style.fontSize = "16px";
  } else {
    doc.addEventListener("DOMContentLoaded", function(e) {
      doc.body.style.fontSize = "16px";
    }, false);
  }
})(750, 750);

方法2

        setRem();
        window.addEventListener("onorientationchange" in window ? "orientationchange" : "resize", function () {
            setRem();
        });
        function setRem() {
            var html = document.querySelector("html");
            var width = html.getBoundingClientRect().width;
            html.style.fontSize = width / 10 + "px"; //1rem = 75px;
        }
        window.onresize = function () {
            setRem();
        }

pc端跳轉(zhuǎn)

        function browserRedirect() {
            var sUserAgent = navigator.userAgent.toLowerCase();
            var bIsIpad = sUserAgent.match(/ipad/i) == "ipad";
            var bIsIphoneOs = sUserAgent.match(/iphone os/i) == "iphone os";
            var bIsMidp = sUserAgent.match(/midp/i) == "midp";
            var bIsUc7 = sUserAgent.match(/rv:1.2.3.4/i) == "rv:1.2.3.4";
            var bIsUc = sUserAgent.match(/ucweb/i) == "ucweb";
            var bIsAndroid = sUserAgent.match(/android/i) == "android";
            var bIsCE = sUserAgent.match(/windows ce/i) == "windows ce";
            var bIsWM = sUserAgent.match(/windows mobile/i) == "windows mobile";
            //document.writeln("您的瀏覽設(shè)備為：");
            if (bIsIpad || bIsIphoneOs || bIsMidp || bIsUc7 || bIsUc || bIsAndroid || bIsCE || bIsWM) {
                window.location.href="xxx.com"; //請(qǐng)?jiān)诖颂幪顚?xiě)移動(dòng)端的網(wǎng)址
            }
        }
        //執(zhí)行跳轉(zhuǎn)
        browserRedirect();

動(dòng)態(tài)傳參

//designWidth:設(shè)計(jì)稿的實(shí)際寬度值，需要根據(jù)實(shí)際設(shè)置
//maxWidth:制作稿的最大寬度值，需要根據(jù)實(shí)際設(shè)置
//這段js的最后面有兩個(gè)參數(shù)記得要設(shè)置，一個(gè)為設(shè)計(jì)稿實(shí)際寬度，一個(gè)為制作稿最大寬度，例如設(shè)計(jì)稿為750，最大寬度為750，則為(750,750)
;(function(designWidth, maxWidth) {
  var doc = document,
    win = window,
    docEl = doc.documentElement,
    remStyle = document.createElement("style"),
    tid;

  function refreshRem() {
    var width = docEl.getBoundingClientRect().width;
    maxWidth = maxWidth || 540;
    width>maxWidth && (width=maxWidth);
    var rem = width * 100 / designWidth;
    remStyle.innerHTML = 'html{font-size:' + rem + 'px;}';
  }

  if (docEl.firstElementChild) {
    docEl.firstElementChild.appendChild(remStyle);
  } else {
    var wrap = doc.createElement("div");
    wrap.appendChild(remStyle);
    doc.write(wrap.innerHTML);
    wrap = null;
  }
  //要等 wiewport 設(shè)置好后才能執(zhí)行 refreshRem，不然 refreshRem 會(huì)執(zhí)行2次；
  refreshRem();

  win.addEventListener("resize", function() {
    clearTimeout(tid); //防止執(zhí)行兩次
    tid = setTimeout(refreshRem, 300);
  }, false);

  win.addEventListener("pageshow", function(e) {
    if (e.persisted) { // 瀏覽器后退的時(shí)候重新計(jì)算
      clearTimeout(tid);
      tid = setTimeout(refreshRem, 300);
    }
  }, false);

  if (doc.readyState === "complete") {
    doc.body.style.fontSize = "16px";
  } else {
    doc.addEventListener("DOMContentLoaded", function(e) {
      doc.body.style.fontSize = "16px";
    }, false);
  }
})(750, 750);