Question

i have the following Problem:

I want to know if it is possible to modify default html helper methods, e.g. the Html.BeginForm() method.

I know that i can write a custom helper method where i can add some stuff, but some of them have alot of overloaded functions.

then only thing i would need is, that you can add some custom html string “after” the element was rendered

e.g.:

@using(Html.BeginForm("setDate", "DateController", new { DateId = Model.Date.Identifier }, FormMethod.Post, new { id = "setDateForm" })) {
    @* some input here... *@
}

and after the

<form></form>

i would like to render a validation script, or something else, lets say jQuery validator:

<script>$('#setDateForm').validate();</script>

since i dont want to do that over and over again (maybe i could forget it once..) it would be nice to modify the default Html helper.

If it is not possible i just might have to write my own BeginForm or a wrapper for the EndForm helper :/

Answer 1

As a very basic starting point, you could use something like this:

namespace YourProject.Helpers
{
    public static class HtmlHelperExtensions
    {
        public static IDisposable CustomBeginForm(this HtmlHelper helper, string html)
        {
            return new MvcFormExtension(helper, html);
        }

        private class MvcFormExtension : IDisposable
        {
            private HtmlHelper helper;
            private MvcForm form;
            private string html;

            public MvcFormExtension(HtmlHelper helper, string html)
            {
                this.helper = helper;
                this.form = this.helper.BeginForm();
                this.html = html;
            }

            public void Dispose()
            {
                form.EndForm();
                helper.ViewContext.Writer.Write(this.html);
            }
        }
    }
}

You’d either need to add the namespace in your view or add it to the web.config file in your Views folder. After that, you can use it like so:

@using (Html.CustomBeginForm("<p>test</p>")) {
    // Additional markup here
}

This works for me here but you’d certainly need to customise it to fit your needs, especially as you’ll likely want to pass additional parameters to Html.BeginForm().