whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  1. TResult? $default(
    1. String appId,
    2. String userId,
    3. String orderNo,
    4. @JsonKey.new(name: 'version') String apiVersion,
    5. String nonce,
    6. String sign,
    )?
)

A variant of when that fallback to returning null

It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case _:
    return null;
}

Implementation

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>(TResult? Function( String appId,  String userId,  String orderNo, @JsonKey(name: 'version')  String apiVersion,  String nonce,  String sign)?  $default,) {final _that = this;
switch (_that) {
case _OcrRequest() when $default != null:
return $default(_that.appId,_that.userId,_that.orderNo,_that.apiVersion,_that.nonce,_that.sign);case _:
  return null;

}
}