In this article I will explain with an example, how to display Validation Summary in ASP.Net MVC Razor.
The Validation Summary will display error messages using the Html.ValidationSummary Html Helper function in ASP.Net MVC Razor.
 
 
Configuring Bundles and enabling Client Side Validation
Please refer the following article for complete information on how to configure Bundles and enable Client Side validation in ASP.Net MVC project.
Using Bundles (ScriptBundle) in ASP.Net MVC Razor
Note: By default, the validation done using Data Annotation attributes is Server Side. And hence to make it work Client Side, the Client Side validation must be enabled.
 
 
Model
The following Model class consists of two properties i.e. Name and Age to which the following validation Data Annotation attributes have been applied.
The Required Data Annotation attribute has been specified with a property ErrorMessage with a string value. As the name suggests, this string value will be displayed to the user when the respective validation fails.
public class PersonModel
{
    [Display(Name = "Name")]
    [Required(ErrorMessage = "Name is required.")]
    public string Name { get; set; }
 
    [Display(Name = "Age")]
    [Required(ErrorMessage = "Age is required.")]
    public int Age { get; set; }
}
 
 
Controller
The Controller consists of two Action methods.
Action method for handling GET operation
Inside this Action method, simply the View is returned.
 
Action method for handling POST operation
Inside this Action method, simply the View is returned.
public class HomeController : Controller
{
    // GET: Home
    public ActionResult Index()
    {
        return View();
    }
 
    [HttpPost]
    public ActionResult Index(PersonModel person)
    {
        return View();
    }
}
 
 
View
Inside the View, in the very first line the PersonModel class is declared as Model for the View.
The View consists of an HTML Form which has been created using the Html.BeginForm method with the following parameters.
ActionName – Name of the Action. In this case the name is Index.
ControllerName – Name of the Controller. In this case the name is Home.
FormMethod – It specifies the Form Method i.e. GET or POST. In this case it will be set to POST.
Inside the View, the following three HTML Helper functions are used: -
1. Html.LabelFor – Displaying the Model property name.
2. Html.TextBoxFor – Creating a TextBox for the Model property.
3. Html.ValidationSummary – The ValidationSummary will be used for displaying the Validation Error messages of the Data Annotation Attributes.
There is also Submit button which when clicked, the Form gets submitted.
The jQuery and the jQuery Validation script bundles are rendered at the end of the Model using the Scripts.Render function.
@model ValidationSummary_MVC.Models.PersonModel
 
@{
    Layout = null;
}
 
<!DOCTYPE html>
 
<html>
<head>
    <meta name="viewport" content="width=device-width"/>
    <title>Index</title>
    <style type="text/css">
        body {
            font-family: Arial;
            font-size: 10pt;
        }
        .error {
            color: red;
        }
    </style>
</head>
<body>
    @using (Html.BeginForm("Index", "Home", FormMethod.Post))
    {
        <table>
            <tr>
                <td>@Html.LabelFor(m => m.Name)</td>
                <td>@Html.TextBoxFor(m => m.Name)</td>
            </tr>
            <tr>
                <td>@Html.LabelFor(m => m.Age)</td>
                <td>@Html.TextBoxFor(m => m.Age)</td>
            </tr>
            <tr>
                <td></td>
                <td><input type="submit" value="Submit"/></td>
                <td></td>
            </tr>
        </table>
        @Html.ValidationSummary(false, "", new { @class = "error" })
    }
</body>
@Scripts.Render("~/bundles/jquery")
@Scripts.Render("~/bundles/jqueryval")
</html>
 
 
Screenshot
Display Validation Summary in ASP.Net MVC
 
 
Downloads
Download Code