Get checked checkbox MVC5 - asp.net

Question

I have searched some articles but none of them fits with my problem. i have this code in my cshtml
#model IEnumerable<MonitoreoIntegrado.Models.Sensores>
#using (Html.BeginForm("Graphics", "Datos_extensometro", FormMethod.Post, new { #class = "form-horizontal", role = "form" }))
{
#Html.AntiForgeryToken()
<div style="margin:0; padding:0; border:none; position:absolute; bottom:5px; right:25px;"><input type="submit" id="enviar" class="btn btn-primary" value="Consultar"></div>
<div style="float:left; width:428px; height:105px; padding:5px; overflow-y: scroll;">
<h4 style="margin-top:0px;">Consultar multiples sensores</h4>
#foreach (var item in Model)
{
#Html.CheckBox("sensoresCB", false, new { value = #item.idSensor.ToString() }) #item.nombre <a class="moverse" objetivo="#(item.idSensor)" href=""><span class="glyphicon glyphicon-map-marker" title="Ir al marcador"></span></a><br />
}
</div>
}
and this in my controller:
[HttpPost]
[ValidateAntiForgeryToken]
[Authorize(Roles = RolesSistema.Administrador + "," + RolesSistema.Lectura)]
public ActionResult Graphics()
{
return View();
}
I need help to receive that checkboxes in my controller and check which of them are checked

Answer 1

You should use unique id's for your inputs. The easiest way:
#for (var i = 0; i < Model.Count(); i++)
{
#Html.CheckBox("sensoresCB["+i.ToString()+"]", false, new { value = Model[i].idSensor.ToString() })
//your other stuff
}
And on controller side:
[HttpPost]
[ValidateAntiForgeryToken]
[Authorize(Roles = RolesSistema.Administrador + "," + RolesSistema.Lectura)]
public ActionResult Graphics(bool[] sensoresCB) //note this
{
return View();
}
So you got the array with your selections. Use index to understand what checkbox it is.

Answer 2

You could extend the model of item with a Checked property or similar.
public class GraphicsViewModel {
public GraphicsItemViewModel[] Items { get; set; }
}
public class GraphicsItemViewModel {
public bool Checked { get; set; }
public long IdSensor { get; set; }
}
Then you can render the checkbox with a binding to this Checked property.
#model GraphicsViewModel
#using (Html.BeginForm(/* ....*/) {
// use a for loop so the array is bound correctly
#for (int i = 0; i < Model.Items.Length; i++) {
#Html.CheckBoxFor(m => m.Items[i].Checked)
// post back IdSensor value so we can access it in the controller
#Html.HiddenFor(m => m.Items[i].IdSensor)
}
}
Your controller should accept a model for the POST data, you can reuse the ViewModel:
[HttpPost]
public ActionResult Graphics(GraphicsViewModel postData) {
bool areAllChecked = postData.Items.All(i => i.Checked);
bool isFirstChecked = postData.Items.First().Checked;
bool isCertainIdChecked = postData.Items.Single(i => i.IdSensor == 1337).Checked;
// ...
}

Answer 3

I would like to mention a helpful point here, that is
If a checkbox is checked, then the postback values will contain a
key-value pair of the form [InputName]=[InputValue]
If a checkbox is not checked, then the posted form contains no
reference to the checkbox at all.
So in a controller action method, you can use the name of the checkbox and get the values which is only checked
ex:
public ActionResult Graphics(bool[] sensoresCB)
{
return View();
}
Hope above information was helpful
Thanks
Karthik

Answer 4

Based on #teo van kot reply I achieved to recover the checkboxes values. This is my working code.
Controller:
[HttpPost]
[ValidateAntiForgeryToken]
[Authorize(Roles = RolesSistema.Administrador + "," + RolesSistema.Lectura)]
public ActionResult Graphics(int[] sensoresCB)//you can receive a string[] as well
{
//code and stuff
return View();
}
View:
#model IEnumerable<MonitoreoIntegrado.Models.Sensores>
#using (Html.BeginForm("Graphics", "Datos_extensometro", FormMethod.Post, new { #class = "form-horizontal", role = "form" }))
{
#Html.AntiForgeryToken()
//some code stuff
#{
int i = 0;
foreach (var item in Model)
{
#Html.CheckBox("sensoresCB[" + i.ToString() + "]", false, new { value = item.idSensor.ToString() }) #item.nombre<br />
i++;
}
}
}