Question

I want to hide drop down according to class property value in asp.net mvc 3 razar view

Answer 1

You could apply a CSS class to the dropdown:

@Html.DropDownListFor(x => x.SelectedItemId, Model.Items, new { @class = "hidden" })

and then define the hidden CSS class:

.hidden {
    display: none;
}

This hidden class could of course be applied dynamically based on some property value of the view model. For example you could write a custom HTML helper which could be used like so:

@Html.DropDownListFor(
    x => x.SelectedItemId, 
    Model.Items, 
    Html.GetHtmlAttributes(Model.IsHidden)
)

where the GetHtmlAttributes is a custom extension method that you could write:

public static class HtmlExtensions
{
    public static RouteValueDictionary GetHtmlAttributes(bool isHidden)
    {
        if (!isHidden)
        {
            return null;
        }

        return new RouteValueDictionary(new { @class = "hidden" });
    }
}