Forms
In Yii2, we can dynamically generate rich HTML5 forms based upon our model using the yii/widgets/ActiveForm class. The yii/widgets/ActiveForm class has several advantages over managing forms manually. In addition to providing several useful helper methods and pairing well with the HTML helper yii/helpers/Html, forms can be generated from the Gii tool using our model data. When working with models and active record instances, this is the preferred way to generate forms.
Generating forms with Gii
Like Active Record classes, forms can be generated automatically for us from both the web Gii tool and the console Gii tool. Let's take a look at generating a form for authentication, which we'll call LoginForm, and a form to handle registration, which we'll call RegisterForm.
Generating forms with Gii's web interface
For our LoginForm form, let's start by opening up the Gii web tool by navigating to the /gii endpoint of our application and then clicking on the Start button underneath the Form Generator...
