A first take on a C# HtmlFormHelper with client and server side validation

I have been looking for a pretty basic way of automating creation of Html Forms from C#. There’s ofcourse the MVC-way with scaffolding. But I’m not happy with that. I want to easily create my html tag setup in code and add / edit the fields and validation rules in a DRY way. If someone knows of an existing project of this kind, please let me know.

EDIT : HtmlFormsHelper has evolved into “DynaForms” (repo at GitHub), I will be blogging about it soon.

(A complete rewrite of this approach I made before.)

Also read the followup CRUD sample together with NancyFx and SisoDb.

So I wrote a ~300 Loc’s helper class with which this code is all that is necessary to create basic form which maps to a poco:

@using HtmlFormHelpers

    // Define the class somewhere
    public class MyClass
        public int Id { get; set; }
        public string Name { get; set; }
        public string Nickname { get; set; }
        public string EmailAddress { get; set; }
<style type="text/css">
    div.labelinput, div.submit {clear:both;}
    .labelinput label {width:100px;display:block;float:left;}
    .labelinput input {width:200px;display:block;float:left;}        

    // initiate the form helper object

    var form = new HtmlFormDescriptor("myclass-form");

    // Add some fields with optional validation rules, the helper will map the field names to the model field names

    form.Add("Name", required: true);
    form.Add("EmailAddress", labelText: "E-mail address", required: true, email: true);
    form.Add("Submit", type:"submit");

    // instantiate the model class

    var myClass = new MyClass();
    string view="";
    if (IsPost)

        // update and validate the model

        var validationResult = form.TryUpdateModel<MyClass>(Request.Form, ref myClass);
        if (!validationResult.IsValid)
            view = form.Html(myClass);
            // the model is valid - proceed with it to a db or whatever
            view ="<div>Valid!</div>";
        view = form.Html();

@* To enable client side validation using jQuery validate - just add librefs + one row: *@

<script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.5.2.min.js"></script>
<script type="text/javascript" src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.8/jquery.validate.min.js"></script>


Here’s a demo

Here’s the full source

Mind it’s still an early version and it’s far away from perfect, I publish it as I hope I can get comments, ideas and collaboration if someone is up to it. It’s easy to create a Gist fork and publish your own version of this little thing.

HtmlFormHelpers Gist

In my previous version I used FluentValidation for the server side validation, it’s still easy to use that instead of my simple validation code, but I missed a nice way to sync the FluentValidation validation rules with client side rules.

2 thoughts on “A first take on a C# HtmlFormHelper with client and server side validation

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