text: function IsPtInPoly(ALon, ALat, APoints) {
    var iSum = 0,
      iCount;
    var dLon1, dLon2, dLat1, dLat2, dLon;
    if (APoints.length < 3) return false;
    iCount = APoints.length;
    for (var i = 0; i < iCount; i++) {
      if (i == iCount - 1) {
        dLon1 = APoints[i].lng;
        dLat1 = APoints[i].lat;
        dLon2 = APoints[0].lng;
        dLat2 = APoints[0].lat;
      } else {
        dLon1 = APoints[i].lng;
        dLat1 = APoints[i].lat;
        dLon2 = APoints[i + 1].lng;
        dLat2 = APoints[i + 1].lat;
      }
      //以下语句判断A点是否在边的两端点的水平平行线之间，在则可能有交点，开始判断交点是否在左射线上
      if (((ALat >= dLat1) && (ALat < dLat2)) || ((ALat >= dLat2) && (ALat < dLat1))) {
        if (Math.abs(dLat1 - dLat2) > 0) {
          //得到 A点向左射线与边的交点的x坐标：
          dLon = dLon1 - ((dLon1 - dLon2) * (dLat1 - ALat)) / (dLat1 - dLat2);
          if (dLon < ALon)
            iSum++;
        }
      }
    }
    if (iSum % 2 != 0)
      return true;
    return false;
  }
  