Question

Lets say a have the following Model

public class FirstModel
{
    public List<SecondModel> SecondModels { get; set; }
}

public class SecondModel
{
    public string Value { get; set; }
}

And this View

@model FirstModel

....
<input name="SecondModels[0].Value" value="test1"/>
<input name="SecondModels[1].Value" value="test2"/>
<input name="SecondModels[2].Value" value="test3"/>
...

The Modelbinding works good. I get the complete Model to my ActionMethod.

But if i remove the item in the middle using, for example, jQuery.

<input name="SecondModels[0].Value" value="test1"/>
<input name="SecondModels[2].Value" value="test3"/>

i lost the SecondModels[2] because the ModelBinder is unable to bind.
So i get only the first (“test1”).

Is there another Syntax or CustomModelBinder which is able to bind this correctly, or do i need to replace the input names after removing the item ?

Thank you very much in advance!

Answer 1

You may use Non-Sequential Model Binding feature of ASP.NET MVC here. In your case, you need something as follows:

<input type="hidden" name="SecondModels.Index" value="0" />
<input name="SecondModels[0].Value" value="test1"/>

<input type="hidden" name="SecondModels.Index" value="2" />
<input name="SecondModels[2].Value" value="test3"/>

For more information, please have a look at Non-Sequential Indices part of Phil Haack’s blog post:

Model Binding To A List