required attribute not working in asp.net mvc

Question

I have a simple strongly-typed view.

@model GoldForGold.Models.LogonModel
@{
    ViewBag.Title = \"Logins\";
    Layout = \"~/Views/Shared/_Layout.cshtml\";         


        

Answer 1

Here is the complete solution:

1. Add the following scripts to your view:

   <script src='@Url.Content("~/Scripts/jquery-1.8.2.js")' type='text/javascript'></script>    
   <script src='@Url.Content("~/Scripts/jquery.validate.js")' type='text/javascript'>         </script>
   <script src='@Url.Content("~/Scripts/jquery.validate.unobtrusive.js")' type='text/javascript'></script>
   

2. Enable Validation in Web.Config:

   <appSettings>
   <add key="ClientValidationEnabled" value="true" />
   <add key="UnobtrusiveJavaScriptEnabled" value="true" />
   </appSettings>
   

3. Add validation element in the view:

   @Html.ValidationMessageFor(model => model.UserName)
   

4. Add Required attribute to you model`s element.

   [Required(ErrorMessage="please enter username")]
   public string UserName { get; set; }
   

Answer 2

For client side validation you need jquery and jquery validation.

after that client side validation must be enabled in config:

<appSettings> 
...
<add key="ClientValidationEnabled" value="true" /> 
<add key="UnobtrusiveJavaScriptEnabled" value="true" /> 

for server side validation you can check your validation state with:

ModelState.IsValid;

Answer 3

My fix for my problem was to use this line of code in the model class.

using System.ComponentModel.DataAnnotations;

be aware that there is another namespace (Microsoft.Build.Framework) that also supports [Required] annotation.

Answer 4

One other thing to be wary of with [Required] is when using it on an integer field, not just when storing a numeric value, but also, say, when storing the id of the selected value of a dropdown/select list.

[Required] won't work in that situation because an integer property can never be null and so always has a default value of zero. [Required] is checking that the property has a value, and zero is considered a value, so the check will pass.

In that case either declare the property as a nullable integer instead:

    [Required]
    public int? LanguageId { get; set; } // note the int is now nullable

or alternatively use the Range attribute to stop zero being an acceptable value:

    [Range(1, int.MaxValue)]
    public int LanguageId { get; set; }

Answer 5

• Steps for solution:

1- Add the scripts to view:

<script src='@Url.Content("~/Scripts/jquery-1.8.2.js")' type='text/javascript'></script>       
<script src='@Url.Content("~/Scripts/jquery.validate.js")' type='text/javascript'>         
</script>
<script src='@Url.Content("~/Scripts/jquery.validate.unobtrusive.js")' type='text/javascript'></script>

2- Enable Validation in Web.Config:

<appSettings>
<add key="ClientValidationEnabled" value="true" />
<add key="UnobtrusiveJavaScriptEnabled" value="true" />
</appSettings>

3- Add validation html helper in the view:

@Html.ValidationMessageFor(model => model.UserName)

4- Add Required attribute to your model`s element:

[Required(ErrorMessage="please enter username")]
public string UserName { get; set; }

Answer 6

For the record, you can include the following code at the end of your view, to make sure that the [Required] attribute pops up in the user interface:

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}