function throttle(fn, delay) {
var timer = null, firstTime = true;
return function () {
if (timer) { return false;}
var that = this;
var args = arguments;
fn.apply(that, args);
timer = setTimeout(function () {
clearTimeout(timer);
timer = null;
}, delay || 500);
};
}
// 防抖
function debounce(fn, delay) {
var timer = null;
return function () {
var that = this;
var args = arguments;
clearTimeout(timer);// 清除重新计时
timer = setTimeout(function () {
fn.apply(that, args);
}, delay || 500);
};
}