Enabling & disabling a textbox in razor view (ASP.Net MVC 3)

I want to Enable or Disable a textbox based on the value (Model.CompanyNameEnabled).

The below code is not working. Please rectify.

@{
    string displayMode = (Model.CompanyNameEnabled) ? "" : "disabled = disabled";
    @Html.TextBox("CompanyName", "", new { displayMode })
}