What are DataAnnotations?
Data annotations (available as part of the System. ComponentModel. DataAnnotations namespace) are attributes that can be applied to classes or class members to specify the relationship between classes, describe how the data is to be displayed in the UI, and specify validation rules.
Which of the below are properties of StringLength?
The StringLength Attribute Specifies both the Min and Max length of characters that we can use in a field. StringLength is somewhat similar to MaxLength and MinLength attribute but operates only on string type properties. Code-First will create the column with the MaxLength size set in this attribute.
Which property of required data Annotation is used to set the Error message On validation?
ValidationAttribute, has an important property, ErrorMessage. This property get or set the custom validation message in case of error.
What is the namespace for data annotation in MVC?
ComponentModel. DataAnnotations Namespace. Provides attribute classes that are used to define metadata for ASP.NET MVC and ASP.NET data controls.
Which namespace contains the DB context class?
The by-convention name is the full name (namespace + class name) of the derived context class. See the class remarks for how this is used to create a connection. Constructs a new context instance using the existing connection to connect to a database.
Which namespaces are required to data annotation using MVC?
Which is the attribute used for validation?
Validation using Data Annotation Attributes
| Attribute | Usage |
|---|---|
| Range | Specifies the numeric range constraints for the value of a property. |
| RegularExpression | Specifies that a property value must match the specified regular expression. |
| CreditCard | Specifies that a property value is a credit card number. |
Which namespace are required to data annotation using MVC?
ComponentModel.DataAnnotations Namespace
ComponentModel. DataAnnotations Namespace. Provides attribute classes that are used to define metadata for ASP.NET MVC and ASP.NET data controls.
What is attribute routing in MVC?
MVC 5 supports a new type of routing, called attribute routing. As the name implies, attribute routing uses attributes to define routes. Attribute routing gives you more control over the URIs in your web application. The earlier style of routing, called convention-based routing, is still fully supported.
What is a context class?
The context class is a most important class while working with EF 6 or EF Core. It represent a session with the underlying database using which you can perform CRUD (Create, Read, Update, Delete) operations. The context class in Entity Framework is a class which derives from System. Data. Entity.
Which namespaces are required to data annotation?
Data annotations are attribute classes that live in the System. ComponentModel. DataAnnotations namespace that you can use to apply to (decorate) classes or properties to enforce pre-defined validation rules.
- Required.
- Regular Expression.
- Range.
- ZipCode.
- DisplayName.
- DisplayFormat.
- Scaffold.
- DataType.
Which attributes are used for validation in MVC?
What is a validator in Java?
A processor that checks an XML document against Schema . A validator object is not thread-safe and not reentrant.
What is maxLength attribute in HTML?
The maxlength attribute defines the maximum number of characters (as UTF-16 code units) the user can enter into an or . This must be an integer value 0 or higher. If no maxlength is specified, or an invalid value is specified, the input or textarea has no maximum length. Any maxlength value must be greater than or equal to the
What happens if there is no maxLength in the input?
If no maxlength is specified, or an invalid value is specified, the input or textarea has no maximum length. Any maxlength value must be greater than or equal to the value of minlength, if present and valid.
What is the max length of a text area?
This must be an integer value 0 or higher. If no maxlength is specified, or an invalid value is specified, the input or textarea has no maximum length. Any maxlength value must be greater than or equal to the value of minlength, if present and valid.