為了解決 label太多,文字會重疊看不清 所以提出這種辦法
核心代碼

1,創建的時候 將label設置為隱藏
2,通過百度地圖監聽事件 , mouseover或onmouseover 觸發顯示
3,通過mouseover 或onmouseover 觸發隱藏
// 創建文本標注對象
var label = new BMap.Label(" "+data.data[i][4]+" ", { offset: new BMap.Size(10, -25) });
label.setStyle({
color: "#fff",
border: "0",
padding: "0",
display: "none",
background: "rgba(66,117,202,0.9)",
fontSize: "12px",
height: "20px",
lineHeight: "20px",
fontFamily: "微軟雅黑"
});
marker.setLabel(label);
marker.addEventListener("mouseover",function(e){
var label = this.getLabel()
label.setStyle({display:"block"});
});
marker.addEventListener("mouseout",function(e){
var label = this.getLabel()
label.setStyle({display:"none"});
});
map.addOverlay(marker); //將標記添加到地圖中
