Flutter http FormatException: Invalid number

Question

I want to post data to an endpoint(woocommerce create order). I use the following code to do this:

var data = {
        'customer_id': int.parse(Data.UserId),

        'billing[first_name]': nameInputController.text,
        'billing[phone]': phoneInputController.text,
        'billing[postcode]': postalCodeInputController.text,
        'billing[address_1]': addressInputController.text,

        'shipping[first_name]': nameInputController.text,
        'shipping[phone]': phoneInputController.text,
        'shipping[postcode]': postalCodeInputController.text,
        'shipping[address_1]': addressInputController.text,

        'customer_note': note,
      };

      var url = Uri.parse(Endpoints.completeOrder);
      var response = await http.post(url, body: data, headers: {
        'Authorization': Data.authToken
      });

but i get the following error:

I/flutter (25924): FormatException: Invalid number (at character 1)
I/flutter (25924): 
I/flutter (25924): ^

When i replace int.parse(Data.UserId) with an string the problem is solved but i need to post customer_id as integer.

Answer 1

Since if you replace it with String the error is removed, try int.tryParse(Data.UserId).toString() to see if it fixes your issue. I would suggest using tryParse instead of parse since you can get a null default value if the parse fails.