百度地图marker点击切换icon以及上一个icon恢复原样

var preMarker;
this.map.addEventListener("click", function (e) {
console.log(e);
if (e.overlay && e.overlay.toString()=='[object Marker]') {
    var myIcon2 = new BMap.Icon(require("https://mapopen-website-wiki.cdn.bcebos.com/markers.png"), new BMap.Size(19, 25), {
        anchor: new BMap.Size(10, 25),
        imageOffset: new BMap.Size(0, 0 - 11 * 25)
    });
    if (typeof (preMarker) != 'undefined') {
        preMarker.setIcon(myIcon2);
    }
    var myIcon = new BMap.Icon(require("https://mapopen-website-wiki.cdn.bcebos.com/markers.png"), new BMap.Size(19, 25), {
        anchor: new BMap.Size(10, 25),
        imageOffset: new BMap.Size(0, 0 - 12 * 25)
    });
    e.overlay.setIcon(myIcon);
    preMarker = e.overlay;
    console.log(preMarker);
}
});