Validation and Data Annotations In MVC 5

Validation and  Data Annotations  In MVC 5

Validation is way to check data or information is authentic or not. Here we are discuses How to validate data or information from client Side Step By step
step 1:
use namespace 
System.ComponentModel.DataAnnotations;
step2:
Create Model class
Let Us consider Create Model Class employee
and some property define as 

public string FirstName { get; set; }

public string LastName { get; set; }

public string Email { get; set; }

public string EmailConfirm { get; set; }

public int Age { get; set; }

public decimal Price { get; set; }

step3

We are Disused Required

 [Required]
public string FirstName { get; set; }

[Required]

public string LastName { get; set; }

[Required]

[StringLength(160)]
public string FirstName { get; set; }

[Required]

[StringLength(160)]

public string LastName { get; set; }

[Required]

[StringLength(160, MinimumLength=3)]

public string FirstName { get; set; }

Step 4:

RegularExpression

Some properties of Order require more than a simple presence or length check. For example, 

you want to ensure the Email property of an  Order contains a valid, working e-mail address. 

Unfortunately, ensuring an e-mail address is working without sending a mail message and waiting 

for a response is practically impossible. What you can do instead is ensure the value  looks  like  a 

working e-mail address using a regular expression:

[RegularExpression(@"[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}")]

public string Email { get; set; }

Range

The  Range attribute specify  minimum and maximum constraints for a numerical value. If the 

 field  only wanted to serve middle-aged customers, you could add an Age  property to the 

Order class and use the  Range attribute as in the following code:

[Range(35,44)]

public int Age { get; set; }

The values are inclusive. The Range attribute can work with integers and doubles, and 

another overloaded version of the constructor takes a  Type parameter and two strings (which can 

allow you to add a range to date and decimal properties, for example).

[Range(typeof(decimal), "0.00", "49.99")]

public decimal Price { get; set; }

Compare:

Compare ensures two properties on a model object have the same value. For example, you might 

want to force customers to enter their e-mail address twice to ensure they didn’t make a typographi-

cal error:

[RegularExpression(@"[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}")]
public string Email { get; set; }

[Compare("Email")]

public string EmailConfirm { get; set; }

[Required]
[DataType(DataType.Password)]
[Display(Name="Password")]
public string Password { get; set; }

Remote

The ASP.NET MVC framework adds an additional Remote validation attribute. This attribute is in the  System.Web.Mvc namespace.

The  Remote attribute enables you to perform client-side validation with a server callback. Take, for example, the  UserName  property of the RegisterModel  class in the MVC Music Store. No two user should have the same  UserName  value, but validating the value on the client to ensure the value is unique is difi cult (to do so you would have to send every single username from the database to the client). With the Remote attribute you can send the  UserName  value to the server, and compare the value against the values in the

database.[Remote("CheckUserName","Account")]

public string UserName { get; set; }