問題：（DRIVING.search是異步操作）
for循環中做異步操作會導致aDistances數組里邊的數據全部都是從A_SHOP_INFO數組中最后一條數據獲取的值。
var iIdx = 0; for(var i=0, len=A_SHOP_INFO.length; i<len; i++){ var shopInfo = A_SHOP_INFO[i]; DRIVING.search(new AMap.LngLat(shopInfo.shop_location_long,shopInfo.shop_location_lat), new AMap.LngLat(myLnglat[0],myLnglat[1]), function(status, result){ var distance = new O_DISTANCE_INFO(); distance.distance = result.routes[0]["distance"]; distance.shop_id = shopInfo.shop_id; distance.shop_location_long = shopInfo.shop_location_long; distance.shop_location_lat = shopInfo.shop_location_lat; distance.shop_location_format_str = shopInfo.shop_location_format_str; // aDistances[aDistances.length] = distance; aDistances.push(distance); iIdx++; if(iIdx == A_SHOP_INFO.length){ // 與所有店鋪導航距離計算完畢 mylog("店鋪距離數組"); mylog("'"+JSON.stringify(aDistances)+"'"); // 計算距離最近的店鋪 //mw_cal_min_distance(aDistances) ; } }); }
解決辦法：可以用$.each來代替for循環
1 //定義變量來計算算出了幾個距離 2 var iIdx = 0; 3 //這里不使用for循環，是因為for循環中發生了異步請求之后，會導致所有異步請求成功之后的shopInfo都是最后一條數據。 4 $.each(A_SHOP_INFO, function(i,shopInfo){ 5 DRIVING.search(new AMap.LngLat(shopInfo.shop_location_long,shopInfo.shop_location_lat), new AMap.LngLat(myLnglat[0],myLnglat[1]), function(status, result){ 6 var distance = new O_DISTANCE_INFO(); 7 distance.distance = result.routes[0]["distance"]; 8 distance.shop_id = shopInfo.shop_id; 9 distance.shop_location_long = shopInfo.shop_location_long; 10 distance.shop_location_lat = shopInfo.shop_location_lat; 11 distance.shop_location_format_str = shopInfo.shop_location_format_str; 12 // aDistances[aDistances.length] = distance; 13 aDistances.push(distance); 14 iIdx++; 15 if(iIdx == A_SHOP_INFO.length){ // 與所有店鋪導航距離計算完畢 16 mylog("店鋪距離數組"); 17 mylog("'"+JSON.stringify(aDistances)+"'"); 18 // 計算距離最近的店鋪 19 // mw_cal_min_distance(aDistances) ; 20 } 21 }); 22 });