Converting .Net Object In To JSON Object ASP.Net MVC

If you want to convert your .Net object in to a JSON object in the view the first thing you can use is to use System.Web.Script.Serialization.JavaScriptSerializer object and convert it in to JSON.

@{
System.Web.Script.Serialization.JavaScriptSerializer serializer = new System.Web.Script.Serialization.JavaScriptSerializer();
//....

<script>

var s = @serializer.Serialize(Model);
</script>

}

This is MVC3 Razor syntax. The problem here is in the @ sign it will again HTML encode the JSON object which lead you to flowing error.

var s = { "Name":"a","Id":1};
Create:228Uncaught SyntaxError: Unexpected token &

To avoid this we can use HTML.Raw() helper method like below.

var s = @HTML.Raw(serializer.Serialize(Model));

The easiest and the most reusable way of doing it is to write a helper method link this,

public static MvcHtmlString ToJson(this HtmlHelper html, object obj)
{
  JavaScriptSerializer serializer = new JavaScriptSerializer();
  return MvcHtmlString.Create(serializer.Serialize(obj));
}

And then in the view we can use this helper method

ASP.Net MVC Submit Collection Of Models

If you are using ASP.Net MVC for your presentation layer there are situations where you want to submit collection of view models. As an example lets say you have view models like this,

Person

• Id : int
• Name : string
• Addresses : Ilist

Address

• Id : Int
• Line1 : string
• City : string
• Type : string

The Person view model has a collection of addresses. 

Then you need to have an edit view for the person to edit all the details of the person view model. In the edit view there will be code like this to display current addresses to the user to edit/ add new or delete .

@model YourNameSpace.Models.Person
@using (Html.BeginForm("Edit", "Person", FormMethod.Post, new { enctype = "multipart/form-data", id = "personEditForm" }))
{
///.................
               @foreach (var address in Model.Addresses)
                   {
                        @Html.HiddenFor(m,address.Id);
                        @Html.EditorForl(m, address.Line1);
                           //............
                   }
//....................................
}

This will generate HTML for the address Id  and address Line1 like this,

…..


…..


……

Because there are several inputs with same name we can't submit all values in the form For that the names should be like "Addresses[0].Line1" as below.

…..


…..


……

Of course you can achieve this by creating an editor template for address. But you will be in trouble when you delete some address in the middle of the sequence. And also if you have more properties like address for the person view model it will abuse your template folder.
This is the solution which I created with help of jQuery. I have written a jQuery function to reset all the names of those collection properties . To get the collection name I have added a wrapper div for each address . Before reset the names the HTML is like this,

…..




…..




……

And then I added this jQuery to onClick event to reset names before submit,

$("#submitButton").click(fuction(){
 $('.collection').each(function (index, domEle) {
           var property=$(this).attr('propertyName');
             $(this).children('div').each(function (index, domEle) {
                 $('input,select',$(this)).each(function (){
                    var oldName;
                
                    var name= $(this).attr('name')+'';
                    var i=  name.indexOf(']');
                    if(i>0){
                         oldName= name.substr(i+2);
                     }else {
                         oldName=  $(this).attr('name');
                         
                     }
                     $(this).attr('name',property+'['+index+'].'+  oldName);
                     $(this).next('span').attr('name',property+'['+index+'].'+  oldName);// need to change the names of validations messages too.
                     $(this).next('span').attr('data-valmsg-for',property+'['+index+'].'+  oldName);
                });
             });
     });   
});

After reeting the names the HTML will be like this,

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…..




……

ASP.Net MVC Client Validation For Dynamically Added Form

This is how I have implemented the client side validation with MVC3 client side validation with JQuery validation plugin. The requirement was to create a model dialog with a form which is loaded via an Ajax request to the server.

1. Enable client validation in web.config

We need to enable client side validation in web.config application settings section like thism

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

    2 The form
 In your form you need to have a FormContext otherwise it will not generate validation attributes.  If the FormContext is null we need to create a new FormContext  like this in your view.

 
@{using (Html.BeginForm("Create", "Person", FormMethod.Post)
  {
      if (this.ViewContext.FormContext == null)
      {
          this.ViewContext.FormContext = new FormContext();
      }
    // .....
  }

    3 Phrase validation attributes 
 Then after the ajax request we need to phrase validation attributes using JQuery like this,<br />

 
$.get("@Url.Action("Create", "Person")", null, function (data) {
         $('#yourDivId').html(data);
         $("form").removeData("validator");
         $("form").removeData("unobtrusiveValidation");
        $.validator.unobtrusive.parse("form");          
   });