對象數組:
var LocationInfoData =[ {_id: "60eea0b998da2545481b78c0", locationName: "澳門海事博物館", region: "澳門特別行政區/風順堂區"},
{_id: "60eea0b398da2545481b66d5", locationName: "媽閣廟", region: "澳門特別行政區/風順堂區"},
{_id: "60eea0b398da2545481b66c1", locationName: "圣奧斯定教堂", region: "澳門特別行政區/風順堂區"},
{_id: "60eea0b398da2545481b66d1", locationName: "圣老楞佐教堂", region: "澳門特別行政區/風順堂區"},
{_id: "60eea0c098da2545481b8c4a", locationName: "鄭家大屋", region: "澳門特別行政區/風順堂區"}]
const res = new Map();
var districts = LocationInfoData.filter((a) => !res.has(a.region) && res.set(a.region, 1));
