Flutter how to check for null values in api response Json when parsing it to dart class, below is my-CodePudding

for the calls where the 'Building object' is null is get this error below,

datatype 'Null' is not a subtype of type 'Map<String, dynamic>'

but for the call where all the data is available, I don't get any error, so how can I make my dart class check for null values without getting the error above, below is my dart class modal.

CodePudding user response：

In model you can define values like paidByNum = json['paidByNum'] ?? defaultValue;

For example if paidByNum is of type int then paidByNum = json['paidByNum'] ?? 0;

For string paidByNum = json['paidByNum'] ?? "";

This will replace the null value with default value.

CodePudding user response：

simply do a null check and assign a default or null

_data['id'] = id == null ? null : id;

PS: typed code is more welcome than screenshots