MVC3 Drop Down or ListBox with dynamic check boxes - asp.net-mvc-3

Question

I have an MVC3 C#.Net web app. I have a requirement to display a list of check boxes (either in a drop down or a List Box) dynamically based on a table in our db. The table can contain 1:500 entries. I then need to pass the selected check boxes to the Controller in order to perform an action on each selection. Any ideas on an implementation?

Answer 1

There are many ways to go about this but here is a general demo.
You can pass a list of the checkbox values and descriptions either on the Model (as this example does), ViewData[""] dictionary or ViewBag (MVC3+).
Then in your view loop through them and add them to your form using the name="chxBxGroupName" to group them.
Now create a controller action to post to that takes a List of the value type (in this example int) with the parameter naming matching the name="chxBxGroupName".
It will post a list of checked values.
The post page will just print out:
123
456
// This is your landing page. It gathers the data to display to the user as checkboxes.
public ViewResult MyPageWithTheCheckboxes()
{
// For example: Assume a Dictionary with the checkbox value and description
// Replace with DB call, etc.
return View(new Dictionary<int, string> { { 123, "Foo" }, { 456, "Bar" } });
}
<%# Page Title="" Language="C#" Inherits="System.Web.Mvc.ViewPage<Dictionary<int,string>>" %>
<!-- Rest of HTML page... -->
<form id="frm1" action="<%=Url.Action("MyPost")%>" method="post">
<% foreach (var item in Model) { %>
<input type="checkbox" id="chxBx<%=item.Key%>" name="chxBxGroupName" value="<%=item.Key%>"/>
<label for="chxBx<%=item.Key%>"><%=item.Value%></label>
<br/><br/>
<% } %>
<input type="submit" value="Go!"/>
</form>
<!-- Rest of HTML page... -->
public ContentResult MyPost(List<int> chxBxGroupName)
{
return Content(string.Join(Environment.NewLine, chxBxGroupName ?? new List<int>()), "text/plain");
}

Answer 2

the answer provided by Jay accomplishes exactly what you need. If you want to put the items in a list you can do it by surrounding the markup with a div control lie below
<div style="height:40px;overflow:auto;">
<% foreach (var item in Model) { %>
<input type="checkbox" id="chxBx<%=item.Key%>" name="chxBxGroupName" value="<%=item.Key% >"/>
<label for="chxBx<%=item.Key%>"><%=item.Value%></label>
<br/><br/>
<% } %>
</div>
unfortunately you cant have checkboxes in a <select />, but if you really wanted it to look like a select list you could add some JQuery that processes onclick of a textbox and shows the div. This obviously would require some jQuery and might not be worth it