// 进度条拖拽开始，不可以前进，可以后退
          let start = true;
          let startProgress = 0;
          let endProgress = 0;
          this.Aliplayer.on('startSeek', (e) => {
            if(start){
              start = false;
              startProgress =  this.Aliplayer.getCurrentTime();
            }
            this.Aliplayer.pause();
          });
          //阿里播放器拖动【结束】拖动时，不可以前进，可以后退
          this.Aliplayer.on('completeSeek', (e) => {
            start = true;
            endProgress =  this.Aliplayer.getCurrentTime();
            if (endProgress < startProgress) {
              this.Aliplayer.seek(endProgress);
            } else {
              this.Aliplayer.seek(startProgress);
            }
            this.Aliplayer.play();
          });