What we shall look at in this lesson is when to reject or accept a users entries.By this I mean should we allow the user to completely fill out the User Form first and then inform him/her that some of their entries are not valid, or would it be better to inform the user at each step.The validation mechanism in Win Forms is somewhat cumbersome, too simple for most cases, and not very well implemented, however when properly used it allows to accomplish different validation scenarios.We have a simple example in our Quick Start Framework application that we will explain in more detail here.Let me throw a couple of UX ideas that use form validation on each change, but that react a bit differently (async ? apparently they hate any form of distraction for the user during their data entry interaction.. NET controls is in the order in which they fire the Lost Focus and Validate events.If it's the last field that is invalid, the user is editing it.
The sequence is the same regardless of how the end user moves the input focus away from the control. NET controls fire these events in the same sequence only if end users move the input focus by means of the keyword; if they use the mouse, the control fires a Lost Focus event, then the Validating event, and – if the validation fails – another Got Focus event to let the application know that the focus is again on the control. NET programs created by VB Migration Partner follow the . In most cases, the fact that the Lost Focus event fires before the Validate event doesn’t affect the application negatively.
This means that if you have Causes Validation set to true inside the textbox, a validation will be triggered only when the textbox loses focus.
Also the control that accepts the focus must have its Causes Validation set to true to be inside the validation process or else it will allow the change of focus.
Take for example the Wizard which we designed earlier.
We placed in some simple validation that checked whether a required entry was made and did not allow the user to move forward to the next step until such time.