asNum method
解析成int或者double值
Implementation
num asNum(String key) {
if (this == null) return 0;
Object? value = this![key];
if (value == null) return 0;
if (value is int) return value;
if (value is double) return value;
try {
if (value is String) {
if (value.contains('.')) {
return double.parse(value);
} else {
return int.parse(value);
}
}
} catch (e) {
print(e);
_print('json parse failed,exception value::\"$key\":$value');
_printDetail('asNum', key, this);
}
return 0;
}