# contains method

1. @override

bool contains(

1. Class? exType

)
override

Checks if this exception or any exception in its cause chain is of the specified type.

### Example:

    if (exception.contains(Class<IOException>())) {
      print('Contains an IO exception in the chain');
    }

## Implementation

    @override
    bool contains(Class? exType) {
      if (super.contains(exType)) {
        return true;
      }
      if (_relatedCauses != null) {
        for (var relatedCause in _relatedCauses) {
          if (relatedCause.runtimeType == exType) {
            return true;
          }
          if (relatedCause is NestedRuntimeException &&
              relatedCause.contains(exType)) {
            return true;
          }
        }
      }
      return false;
    }