Finally, the Display Name attribute is applied to the Date Released property to display an error message like "The Date Released field is required." instead of the error "The Date Released field is required." Note Notice that the proxy properties in the Movie Meta Data class do not need to represent the same types as the corresponding properties in the Movie class.For example, the Director property is a string property in the Movie class and an object property in the Movie Meta Data class.Preventing bad form information is a deadly game of cat and also cat.
Figure 4: Invalid currency amount If you are using the Microsoft Entity Framework to generate your data model classes then you cannot apply the validator attributes directly to your classes.
Because the Entity Framework Designer generates the model classes, any changes you make to the model classes will be overwritten the next time you make any changes in the Designer.
Take advantage of the Data Annotation Model Binder to perform validation within an ASP. Learn how to use the different types of validator attributes and work with them in the Microsoft Entity Framework. Finally, the Unit Price property must match a regular expression pattern that represents a currency amount.
In this tutorial, you learn how to use the Data Annotation validators to perform validation in an ASP. The advantage of using the Data Annotation validators is that they enable you to perform validation simply by adding one or more attributes – such as the Required or String Length attribute – to a class property. Listing 1: Models\The Product class illustrates how to use one additional attribute: the Display Name attribute.
Before you can use the Data Annotation validators, you must download the Data Annotations Model Binder. Next click the Browse tab and browse to the location where you downloaded (and unzipped) the Data Annotations Model Binder sample (see Figure 1). The Display Name attribute enables you to modify the name of the property when the property is displayed in an error message.