dart json相关

例子2：

import 'dart:convert';

void main() {

  String asdf = '{"game":"bi_da_xiao","lev_N":{"rooms":"1","room":[{"num":"1","tables":{"1":"Y","2":"Y"}}]},"lev_M":{"rooms":"2","room":[{"num":"1","tables":{"1":"Y","2":"Y"}},{"num":"2","tables":{"1":"Y","2":"Y"}}]},"lev_H":{"rooms":"3","room":[{"num":"1","tables":{"1":"Y","2":"Y"}},{"num":"2","tables":{"1":"Y","2":"Y"}},{"num":"3","tables":{"1":"Y","2":"Y"}}]}}';

print(json.decode(asdf));
print(json.decode(asdf).runtimeType);

print(json.decode(asdf)["lev_M"]);
print(json.decode(asdf)["lev_M"].runtimeType);

print(json.decode(asdf)["lev_M"]["rooms"]);
print(json.decode(asdf)["lev_M"]["rooms"].runtimeType);

print(json.decode(asdf)["lev_M"]["room"]);
print(json.decode(asdf)["lev_M"]["room"].runtimeType);

print(json.decode(asdf)["lev_M"]["room"][0]);
print(json.decode(asdf)["lev_M"]["room"][0].runtimeType);

print(json.decode(asdf)["lev_M"]["room"][0]["num"]);

print(json.decode(asdf)["lev_M"]["room"][0]["tables"]);

print(json.decode(asdf)["lev_M"]["room"][0]["tables"]["1"]);




}

　　输出：

{game: bi_da_xiao, lev_N: {rooms: 1, room: [{num: 1, tables: {1: Y, 2: Y}}]}, lev_M: {rooms: 2, room: [{num: 1, tables: {1: Y, 2: Y}}, {num: 2, tables: {1: Y, 2: Y}}]}, lev_H: {rooms: 3, room: [{num: 1, tables: {1: Y, 2: Y}}, {num: 2, tables: {1: Y, 2: Y}}, {num: 3, tables: {1: Y, 2: Y}}]}}
_InternalLinkedHashMap<String, dynamic>
{rooms: 2, room: [{num: 1, tables: {1: Y, 2: Y}}, {num: 2, tables: {1: Y, 2: Y}}]}
_InternalLinkedHashMap<String, dynamic>
2
String
[{num: 1, tables: {1: Y, 2: Y}}, {num: 2, tables: {1: Y, 2: Y}}]
List
{num: 1, tables: {1: Y, 2: Y}}
_InternalLinkedHashMap<String, dynamic>
1
{1: Y, 2: Y}
Y

Process finished with exit code 0