Self validating textbox
To specify how validation is to be done, override the validate method.Note that the constructor takes a parent widget, and also allows you to use the value option to specify the initial contents.You may also override yii\validators\Validator::validate Value() instead of ) when attaching validator.
For example, really work, you should declare validation rules for the attributes you plan to validate.Given a model populated with user inputs, you can validate the inputs by calling the yii\base\Model::validate() method.The method will return a boolean value indicating whether the validation succeeded or not.If you only need to perform one type of validation (e.g.validating email addresses), you may call the validate() method of the desired validator, like the following: After validation, you can check if the validation succeeded or not by calling the has Errors() method, and then get the validation errors from the errors property, like you do with a normal model.
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This should be done by overriding the yii\base\Model::rules() method.