[JavaScript]代码    

/**    * 计算一个点是否在多边形里    * @param {Object} pt 标注点    * @param {Object} poly 多边形数组    */    function isInsidePolygon(pt, poly){        for (var c = false, i = -1, l = poly.length, j = l - 1; ++i < l; j = i)             ((poly[i].lat <= pt.lat && pt.lat < poly[j].lat) || (poly[j].lat <= pt.lat && pt.lat < poly[i].lat)) &&            (pt.lng < (poly[j].lng - poly[i].lng) * (pt.lat - poly[i].lat) / (poly[j].lat - poly[i].lat) + poly[i].lng) &&            (c = !c);        return c;    }