Created
January 4, 2021 16:43
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Null aware on JSON response
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| void main() { | |
| var json = { | |
| "k1": [ | |
| { | |
| "m1": ["n1"] | |
| }, | |
| { | |
| "m1": ["n2"] | |
| } | |
| ], | |
| "k2": [ | |
| { | |
| "m1": ["n3"] | |
| } | |
| ] | |
| }; | |
| dynamic mapOrListGet(dynamic map, List path) { | |
| assert(path.length > 0); | |
| assert(map is List || map is Map); | |
| var m = map ?? const {}; | |
| var firstEl = path.removeAt(0); | |
| var result = (m is List) | |
| ? (firstEl < m.length ? m.elementAt(firstEl) : null) | |
| : m[firstEl]; | |
| if (path.length == 0 || result == null) { | |
| return result; | |
| } else { | |
| return mapOrListGet(result, path); | |
| } | |
| } | |
| print(mapOrListGet(json, ["k1", 0, "m1", 0])); | |
| print(mapOrListGet(json, ["k1", 0, "m1", 2])); | |
| print(mapOrListGet(json, ["k3", 0, "m1"])); | |
| } |
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