覆盖ASP.NET MVC EditorFor

Question

Is it possible to override ASP.NET MVC's EditorFor and DisplayFor .

I want to apply some logic as to whether or not to actually display the content or simply output "".

So I want to do something like this (pseudocode):

public static MyEditorFor(this html)
{
  if(ICanRender)
  {
    call HtmlEditorFor(original);
  }
  else
  {
    return EmtpyString;
  }
}

Is this possible?

Answer 1

It sound like you want an extension:

public static MvcHtmlString MyEditorFor<TModel, TValue>(this HtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression) {
    if(ICanRender)
    {
        return System.Web.Mvc.Html.EditorExtensions.EditorFor(html, expression);
    }
    else
    {
        return MvcHtmlString.Create(string.Empty);
    }
}

That codesnipped is untested but it should work.

Answer 2

You can create your own Html helpers as extensions methods for HtmlHelper or HtmlHelper<TModel> . Simply add extension method like below:

public static MvcHtmlString MyEditorFor<TModel, TProperty>(
    this HtmlHelper<TModel> htmlHelper,
    Expression<Func<TModel, TProperty>> expression)
{

}

Of course, you can add additional parameters as needed. Inside this method access all methods of htmlHelper . Return ordinary EditorFor for example:

public static MvcHtmlString MyEditorFor<TModel, TProperty>(
    this HtmlHelper<TModel> htmlHelper,
    Expression<Func<TModel, TProperty>> expression)
{
    return htmlHelper.EditorFor(expression);
}

Or you can create your own element (or combination of them) as you need:

public static MvcHtmlString MyEditorFor<TModel, TProperty>(
    this HtmlHelper<TModel> htmlHelper,
    Expression<Func<TModel, TProperty>> expression)
{
    TagBuilder div = new TagBuilder("div");
    div.AddCssClass("some-css");

    MvcHtmlString editor = htmlHelper.TextBoxFor(expression);
    div.InnerHtml = editor.ToHtmlString();

    return new MvcHtmlString(div.ToString());
}

Read more about TagBuilder here .

Answer 3

You could put the custon models under the "views/shared/EditorTemplates" or "views/shared/DisplayTemplates", and put the files with the [Model name].cshtml.

Ex: DateTime.cshtml

That way all editors and displays with DateTime type defined in your models properties will follow the DateTime.cshtml logic.

The problem is you will have to deal with the HTML in the ViewData.TemplateInfo if you want to retrieve the fields you want.