減少null判斷情況
https://stackoverflow.com/questions/51036758/flutter-the-method-map-was-called-on-null
https://juejin.im/post/5c6d38b1f265da2dcc7feb69
https://cloud.tencent.com/developer/article/1370380
?? => if null
https://blog.csdn.net/ffa_ijj/article/details/85051156
return qres?.map((value) { LinkedHashMap result = json.decode(value["jsonitem"]); return result; })?.first ?? new LinkedHashMap(); 這個判斷方式有個問題，當查詢回來為[]，不是null情況下，在.first會出錯，因為 “No element"會出錯，但.toList()會正確，故改回
if (qres == null || qres.isEmpty) return new Member(); // 待確定是否出錯 var resmap = qres.first; return new Member.fromJson(json.decode(resmap["jsonitem"]));
git global 已設定，但其他專案需要設定其他的帳號
到專案目錄下的.git內，修改config檔案，補上
[user]
name = ooxx
email = ooxx@gmail.com
即可蓋過global
https://github.com/drails-dart/dart-serialise
https://github.com/parnham/dart-serialise
https://github.com/dart-league/dson
windows system path
ANDROID_AVD_HOME
https://javiercbk.github.io/json_to_dart/
https://ashamp.github.io/jsonToDartModel/
https://github.com/fatedier/frp
http://remix.ethereum.org
Not https://remix.ethereum.org
