Checkbox disabled attribute in ASP.NET MVC

It is not easy to achieve this with an if condition inside the helper method because all the below markups will render a disabled chechbox.

<input type="checkbox" disabled>
<input type="checkbox" disabled="disabled">
<input type="checkbox" disabled="false">
<input type="checkbox" disabled="no">
<input type="checkbox" disabled="enabled">

This should work in the razor. Simple If condition and rendering what you want.

@if(item.Selected)
{ 
  @Html.CheckBoxFor(modelItem => item.Selected)
}
else
{
    @Html.CheckBoxFor(modelItem => item.Selected, new { @disabled = "disabled"})
}

You may consider writing a custom html helper which renders the proper markup for this.