A form component can optionally implement a Control Value Accessor, enabling it to read values and listen for changes. Angular comes with a standard provider for handling form controls called Default Value Accessor that works for Inputs, Checkboxes and standard browser elements, we need to add our own implementation for custom controls.
Three methods will need to be implemented to satisfy this interface:.
I have usernames being displayed locally, and therefore I'm trying to prevent email addresses being used. We have a custom plugin that needs to include a required file upload.
Currently, the plugin is not recognizing that a file upload is being attempted. I have a front-end registration page and need to change the validation to add (minimum characters for information on the page and to make fields to accept only letters and other to accept only number ...
SOLUTION To achieve data validation prior the row is committed, you can handle the Cell Validating event, which is raised by the control when the current cell changes or when it goes out of edit mode.
Just wondering if theres anyway to force some validation on the username?
However, pressing the Esc key in this situation will revert the initial value of the cell and it will close the editor. The Row Validating event has a slightly different behavior.
When the validation fails, the editor is closed, but the user cannot change the current row in the grid until a valid cell value is entered.
It is therefore recommended to provide a disabled option with an empty value, as demonstrated in the example above.
Using form events, you may modify information or fields at different steps of the workflow: from the population of the form to the submission of the data from the request.