Self validating models mvc
The following illustration shows a new-user form that is displaying an error message that indicates that the requested ID is not available.The ID that users enter is validated as soon as they leave the text box (that is, when the text box loses focus). As an example of remote validation, this topic shows how to implement a form similar to the one in the previous illustration.Figure 04: Prebinding Validation Errors(Click to view full-size image) There are actually two types of validation error messages - those generated before the HTML form fields are bound to a class and those generated after the form fields are bound to the class.In other words, there are prebinding validation errors and postbinding validation errors.
The default model binder cannot bind the string "apple" to the Price property of the Product class. Therefore, the model binder adds an error to model state.In other tutorials, we'll discuss various strategies for moving your validation code out of your controllers and into your model classes.Note The feedback system for this content will be changing soon. If content within a comment thread is important to you, please save a copy.The goal of this tutorial is to explain how you can perform validation within an ASP. For example, you learn how to prevent someone from submitting a form that does not contain a value for a required field.You learn how to use model state and the validation HTML helpers.
If you submit the HTML form for creating a Product, and you enter an invalid value for the price field and no value for the Units In Stock field, then you'll get the validation messages displayed in Figure 4.