# getDirtyInput Retrieves only the dirty input values of a specific field or the entire form. Object keys whose subtree contains no dirty descendant are omitted; arrays are treated as atomic and returned in full whenever any descendant is dirty. Returns `undefined` if no field in the inspected subtree is dirty. ```ts const input = getDirtyInput(form); const input = getDirtyInput(form, config); ``` ## Generics - `TSchema` - `TFieldPath` ## Parameters - `form` - `config` ### Explanation The `form` parameter is the form store to retrieve dirty input from. The optional `config` parameter scopes the result to a specific field path - if omitted, returns dirty input from the entire form. The returned value is a partial of the inspected input shape containing only the fields whose `isDirty` flag is set, which is useful for submitting only the values that changed since the start input. Arrays are treated as atomic — when any descendant of an array is dirty, the full current array is returned. Internally, the function walks the form's field tree and asks `getFieldBool` whether each branch contains a dirty descendant. Because that check is itself recursive, the cost is effectively linear in field count for typical balanced forms (shallow and wide) and degrades toward `O(N²)` for deeply nested trees. Call this method from submit or blur handlers rather than from tight reactive loops on large forms. ## Returns - `result` ## Related ### Methods