// 节流：持续触发也执行，只不过触发的频率变低了。
/* const throttle = (fn, time) => {
            // #1
            let bBar = true
            return function (e) {
                // #2
                if (bBar) {
                    // #3
                    bBar = false
                    setTimeout(() => {
                        fn.call(this, e)
                        // #4
                        bBar = true
                    }, time)
                }
            }
        } */

/* const throttle = (fn, time) => {
            // #1
            let bBar = true
            return function (e) {
                // #2
                if (!bBar) return
                // #3
                bBar = false
                setTimeout(() => {
                    fn.call(this, e)
                    // #4
                    bBar = true
                }, time)
            }
        } */

// 需求：封装一个 throttle 函数来实现节流的效果
oDiv.onmousemove = _.throttle(function (e) {
  let left = e.pageX - this.offsetLeft
  let top = e.pageY - this.offsetTop
  this.innerHTML = `x: ${left}，y: ${top}`
}, 500)