如果您在formGroup上使用setValue，但没有为该组中的每个控件传递值，则可能会出现此错误.例如:

This error can appear if you're using setValue on a formGroup but not passing in a value for every control within that group. For example:

let group = new FormGroup({
  foo: null, 
  bar: null
});
group.setValue({foo: 'only foo'}); //breaks
group.setValue({foo: 'foo', bar: 'bar'}); //works

如果您确实只想更新组中的控件的 some ，则可以使用patchValue代替:

If you truly want to only update some of the controls on the group, you can use patchValue instead:

group.patchValue({foo: 'only foo, no problem!'});

setValue和patchValue的文档此处