我有一些可以在ios上播放和暂停的视频，但是不能正确倒带或快进。当您尝试快进20秒时，视频将始终进入视频的20秒。我看到ios在currenttime方面遇到了麻烦，但是我不确定如何将这些知识整合到我的代码中。有人可以帮忙吗？
javascript：
let vid;
document.addEventListener('DOMContentLoaded', init);
function init(){
var btnsPlay = document.getElementsByClassName('btnPlay');
var btnsSound = document.getElementsByClassName('btnSound');
var btnsRew = document.getElementsByClassName('btnRew');
var btnsFF = document.getElementsByClassName('btnFF');
for(var i = 0; i < btnsPlay.length; i++) {
btnsPlay[i].addEventListener("click", play);
btnsSound[i].addEventListener("click", sound);
btnsRew[i].addEventListener("click", rew);
btnsFF[i].addEventListener("click", ff);
}
}
function play(ev){
var thisVideo = this.parentNode.parentNode.children[1]; //this button's video
var vid = thisVideo;
let mediaType = vid.type;
let str = vid.canPlayType("video/mp4");
vid.volume = 0.9; // 0 - 1
vid.muted = true;
if(! vid.paused){
vid.pause();
this.firstChild.classList.remove("fa-play");
this.firstChild.classList.add("fa-pause");
} else {
vid.play()
.then(()=>{
this.firstChild.classList.remove("fa-pause");
this.firstChild.classList.add("fa-play");
})
.catch((err)=>{
console.log( {err} );
});
}
}
function sound(ev){
var thisVideo = this.parentNode.parentNode.children[1]; //this button's video
var vid = thisVideo;
//console.log(this.parentNode.parentNode.children[3]);
if (vid.muted) {
vid.muted = false;
this.firstChild.classList.remove("fa-volume-mute");
this.firstChild.classList.add("fa-volume-up");
//document.getElementsByClassName('display-captions').style.opacity = 0;
//$('.display-captions').css('opacity',"0");
this.parentNode.parentNode.children[3].style.opacity = 0;
} else {
vid.muted = true;
this.firstChild.classList.remove("fa-volume-up");
this.firstChild.classList.add("fa-volume-mute");
this.parentNode.parentNode.children[3].style.opacity = 1;
}
}
function rew(ev){
var thisVideo = this.parentNode.parentNode.children[1]; //this button's video
var vid = thisVideo;
if(isiOS) {
vid("canplaythrough",function() {
vid("progress",function() {
vid.currentTime = seekToInitially;
//????
});
});
}
if( ! vid.fastSeek ){
vid.currentTime -= 20;
}else{
vid.fastSeek(-20)
.then(()=>{
})
.catch(err=>{
console.log({err});
})
}
}
function ff(ev){
var thisVideo = this.parentNode.parentNode.children[1]; //this button's video
var vid = thisVideo;
if( ! vid.fastSeek ){
vid.currentTime += 20;
}else{
vid.fastSeek(20)
.then(()=>{
})
.catch(err=>{
console.log({err});
})
}
}