js解决ios 双指缩放、双击放大、移动的兼容性问题

window.onload = function() { // 阻止双击放大 
var lastTouchEnd = 0;
 document.addEventListener('touchstart', function(event) {
if (event.touches.length > 1) { 
event.preventDefault(); 
} });
 document.addEventListener('touchend', function(event) { 
var now = (new Date()).getTime(); if (now - lastTouchEnd <= 300) {
 event.preventDefault(); 
} lastTouchEnd = now;
 }, false); 
// 阻止双指放大 
document.addEventListener('gesturestart', function(event) { event.preventDefault(); }); }

document.body.addEventListener('touchmove', function (e) {
e.preventDefault(); //阻止默认的处理方式(阻止下拉滑动的效果)
}, {passive: false});