Checkbox list for complex type in asp.net mvc

Question

I have a class:

public class ControllerSecurityModel { public string ControlleName { get; set; } public string DisplayName { get; set; } public List<ActionSecurityModel> actions { get; set; } } public class ActionSecurityModel { public string ActionName { get; set; } public string DisplayName { get; set; } public bool IsChecked { get; set; } } 

and model:

 public class PageRoleModel { public List<ControllerSecurityModel> AllPages { get; set; } public List<ControllerSecurityModel> SelectedPage { get; set; } } 

I want to have a check box for each "ActionSecurityModel", I write below:

 <% using (Html.BeginForm()) {%> <% foreach (var cont in Model.AllPages) {%> <fieldset> <legend> <%= cont.DisplayName %></legend> <% foreach (var act in cont.actions) {%> <%: Html.CheckBoxFor(x => act.IsChecked) %> <%: Html.Label(act.DisplayName) %> <% } %> </fieldset> <% } %> <input type="submit" value="save"/> <% } %> 

and this is my controller action:

  public ActionResult SetRole() { PageRoleModel model = new PageRoleModel(); return View(model); } [HttpPost] public ActionResult SetRole(PageRoleModel model) { return View(model); } 

but when i submit the form, is the model null? How can I check the boxes and save them?

Answer 1

Like this:

 <% using (Html.BeginForm()) { %> <% for (var i = 0; i < Model.AllPages.Count; i++) { %> <fieldset> <legend> <%= Model.AllPages[i].DisplayName %> </legend> <% for (var j = 0; j < Model.AllPages[i].actions.Count; j++ ) { %> <%= Html.CheckBoxFor(x => x.AllPages[i].actions[j].IsChecked) %> <%= Html.Label(Model.AllPages[i].actions[j].DisplayName) %> } </fieldset> <% } %> <input type="submit" value="save"/> <% } %> 

To understand why my solution works and yours doesn't, read about the expected wire format , which is used as the default binder for collections. Then view the generated form input field names by looking at the generated HTML source code - you will quickly see the fundamental difference in the name attribute of this check box.

Also, do not expect your entire model to be tied to a POST action. You have only one input field inside your form - a checkbox. So the only value that will be sent to the server and bound to the model. If you need other values, you can include them in hidden fields:

 <!-- in the outer loop: --> <% =Html.HiddenFor(x => x.AllPages[i].DisplayName) %> ... <!-- and then in the inner loop --> <%= Html.HiddenFor(x => x.AllPages[i].actions[j].ActionName) %> <%= Html.HiddenFor(x => x.AllPages[i].actions[j].DisplayName) %> ... and so on ... 

I also highly recommend that you use editor templates instead of writing these loops in your views. They will automatically take care of creating their own names for your input fields, so you have nothing to worry about. I have gazillions of answers on this topic. Just google my name and add editor templates asp.net mvc to your search and you will get many results.