Validation data in Ext.Model - extjs

Question

Help me please.
Models have built-in support for validations, which are executed against the validator functions in Ext.data.validations.
My code:
Ext.define('User', {
extend: 'Ext.data.Model',
fields: [{
name: 'name',
type: 'string'
},{
name: 'age',
type: 'int'
},{
name: 'phone',
type: 'string'
},{
name: 'gender',
type: 'string'
},{
name: 'username',
type: 'string'
}],
validations: [
{
type: 'length',
field: 'name',
min: 2
},{
type: 'format',
field: 'username',
matcher: /([a-z]+)[0-9]{2,3}/
}]
});
var person = Ext.create('User', {
name: 'Eugene',
username: 'Popov',
gender: 'F',
age: 300,
Married: false
});
console.log(person.get('name'))
person.set('name','U');
console.log(person.get('name'))//U
});
I've read that the model can filter data .
What is the principle of their work?
Why I can write wrong values in my example?
Thanks!

Answer 1

Model validations don't reject changes by themselves. Editing a model through some other component (like stores or grid editors) may provide this feature. Validations only come into play when calling the validate or isValid methods on a model.
If your models are part of a store, you can listen for the store's update event (link to docs). From within the event handler, you can validate the model and reject any changes you want.
// Simple demonstration
store.on('update', function (store, model, operation) {
if (operation === Ext.data.Model.EDIT && !model.isValid()) {
model.reject();
}
});