Using Flutter Form Submit with Optional Parameters

When building forms in Flutter, there are several ways to handle form submission. One of the most popular ways is by using the `FormBuilder` widget, which provides a convenient way to create and manage forms. In this article, we will explore how to use `FormBuilder` with optional parameters to customize its behavior.

Invalidating Fields or Forms

When you want to invalidate fields or forms in your Flutter application, there are several ways to do so. For example, you can use the `invalidateField` method to invalidate a specific field, or the `invalidateForm` method to invalidate the entire form. Both of these methods take an optional parameter that allows you to configure the behavior.

Using Optional Parameters

The `invalidateField` and `invalidateForm` methods both take two optional parameters: `shouldValidate` and `shouldNotify`. The `shouldValidate` parameter determines whether the form should be validated when it is invalidated, while the `shouldNotify` parameter determines whether the form should notify its parent widget of the change.

Example Code

Here is an example of how you can use the `invalidateField` method with optional parameters:

```

FormBuilder form = FormBuilder();

form.addField('email', validator: validateEmail);

form.addField('password', validator: validatePassword);

// Invalidate the email field and set shouldValidate to true

form.invalidateField('email', shouldValidate: true);

// Invalidate the password field and set shouldNotify to false

form.invalidateField('password', shouldNotify: false);

```

In this example, we create a `FormBuilder` instance and add two fields: an email field and a password field. We then use the `invalidateField` method to invalidate each field, setting the `shouldValidate` parameter to true for the email field and the `shouldNotify` parameter to false for the password field.

In this article, we have explored how to use Flutter Form Submit with optional parameters to customize its behavior. We have seen how to invalidate fields or forms, and how to use optional parameters to configure the behavior of these methods. By using these techniques, you can create more complex and customized forms in your Flutter applications.

* Use `FormBuilder` to create and manage forms in Flutter.

* Invalidating fields or forms is a common task when building forms.

* Use optional parameters with the `invalidateField` and `validateForm` methods to customize their behavior.

* Configure the form's behavior by setting the `shouldValidate` and `shouldNotify` parameters.

Flutter form submit