<script>
???????function calculatescale() {
???????????var phoneWidth = parseInt(window.screen.width);
???????????var phoneScale = phoneWidth / 1280;//除以的值按手机的物理分辨率
???????????var ua = navigator.userAgent;
???????????var viewportmetacontent = "";
???????????if (/Android (\d+\.\d+)/.test(ua)) {
???????????????var version = parseFloat(RegExp.$1);
???????????????if (version > 2.3) { // andriod 2.3以上
???????????????????viewportmetacontent=‘width=device-width,initial-scale=‘ + phoneScale + ‘,minimum-scale=‘ + phoneScale + ‘,user-scalable=yes‘;
???????????????} else {
???????????????????viewportmetacontent=‘width=device-width,user-scalable=yes‘;
???????????????}
???????????????// 其他系统
???????????} else {
???????????????viewportmetacontent = ‘width=device-width, initial-scale=‘ + phoneScale + ‘,minimum-scale=‘ + phoneScale + ‘,user-scalable=yes‘;
???????????}
???????????return viewportmetacontent;
???????}
???????document.write(‘<meta name="viewport" content="‘+calculatescale()+‘">‘);
???</script>
window.addEventListener(‘orientationchange‘, function (event) {
???????????????var viewportmeta = document.querySelector(‘meta[name="viewport"]‘);
???????????????if (viewportmeta) {
???????????????????viewportmeta.content = calculatescale();
???????????????}
???????????});
web网站在不同设备下进行缩放
原文地址：https://www.cnblogs.com/cathyxiao/p/9151704.html