Question

I have a requirement to add conditional disabled & class attributes to a dropdown form element. I have the following however it does not write out either of the attributes in any state. Is there a way around this.

<%=  Html.DropDownList('--Choose Make--', 'models', ViewData['model_disabled'] == 'false' ? new { @disabled = 'disabled', @class = 'test' } : null)%>   

Answer 1

The problem is:

ViewData['model_disabled'] == 'false' 

The return from ViewData[] is object. Calling == with two objects compares their identity (i.e., are they the exact same object instance), not their equality (i.e., are the strings the same value).

You can try this instead:

((string)ViewData['model_disabled']) == 'false' 

Edit:

A slightly cleaner syntax is available with the MvcContrib ViewData extensions:

ViewData.Get<string>('model_disabled') == 'false' 

Although this feels a little cleaner, you’ll also notice it’s slightly longer. :-p