this is my Model1 class
namespace chetan.Models
{
public class Model1
{
public string selectedItem { get; set; }
public IEnumerable<SelectListItem> items { get; set; }
}
}
this is my controller class
public class HomeController : Controller
{
private rikuEntities rk = new rikuEntities();
public ActionResult Index()
{
var model = new Model1
{
items = new[]
{
new SelectListItem { Value = "Theory", Text = "Theory" },
new SelectListItem { Value = "Appliance", Text = "Appliance" },
new SelectListItem { Value = "Lab", Text = "Lab" }
}
}; return View(model);
}
public ActionResult viewToController(Model1 m)
{
string getSelectedName = m.selectedItem;
return Content(getSelectedName);
}
}
this is my view...
#using (Html.BeginForm("viewToController", "Home"))
{
#Html.ValidationSummary(true)
<fieldset>
<legend>emp</legend>
<div class="editor-field">
#Html.DropDownListFor(x => x.selectedItem,
new SelectList(Model.items, "Value", "Text"))
</div>
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}
i want to add a drop downlist and i want to use selected value in viewToController action of homeController. and there is also one error in View page is "an expression tree may not contain dynamic operation" in (x=>x.selectedItem). Please solve my problem .
I don't understnad what you exactly need. You want to dynamicly add items to the drop down from the database?
I'm big fan of jQuery. You can do everything what you want with HTML using jQuery. So if you are looking how to automaticly add items to the drop down, take look at this: How do I add options to a DropDownList using jQuery?
Related
I am basically trying to display a dropdownlist on my data entry view, and the dropdownlist keeps giving me the error "An expression tree may not contain a dynamic operation". I have added "#Model MyModel" to the top of my view, but still can't get past this error. Does anyone have an idea of how to resolve this issue? I have a controller that looks like this
using MvcApplication1.Models;
namespace MvcApplication1.Controllers
{
public class MyController : Controller
{
public ActionResult Index()
{
return View();
}
public ActionResult EnterInfo()
{
GetUT myGetUT = new GetUT();
ViewBag.uts = GetOptions();
return View(myGetUT);
}
[HttpPost]
public ActionResult EnterInfo(GetUT myGetUT)
{
ViewBag.uts = GetOptions();
return View(myGetUT);
}
private List<UT> GetOptions()
{
List<UT> uts = new List<UT>();
uts.Add(new UT() { ID = 1, Name = "1st" });
uts.Add(new UT() { ID = 2, Name = "2nd" });
uts.Add(new UT() { ID = 3, Name = "3rd" });
uts.Add(new UT() { ID = 4, Name = "4th" });
return uts;
}
}
}
and a view that looks like
#Model MyModel
#{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<title>EnterInfo</title>
</head>
<body>
<div>
#Html.DropDownListFor(x => x.UTID, new SelectList(ViewBag.uts, "ID", "Name", Model.UTID))
Enter an Amount :-<input type="text" name="Amount" /><br />
<input type="submit" value="Submit Info" />
</div>
</body>
</html>
Thanks for all the help.
Well, ViewBag is a dynamic type, so I assume that is what it is complaining about. Try putting public List<UT> UTs { get; set; } as a property on MyModel and change your helper to use the UTs property from your model. Like this:
Controller:
public ActionResult EnterInfo()
{
GetUT myGetUT = new GetUT();
myGetUT.UTs = GetOptions();
return View(myGetUT);
}
View:
#Html.DropDownListFor(x => x.UTID,
new SelectList(Model.UTs, "ID", "Name", Model.UTID))`
Edit: If it isn't obvious, your view should be typed to a GetUT type (because that's what you are passing in to the View() function in the EnterInfo action) - I assume that's what you mean when you said #Model MyModel. If not, change it to #Model GetUT and put the property on the GetUT class.
So I have the following code:
#model Project.Models.ViewModels.SomeViewModel
#using (Html.BeginForm("SomeAction", "SomeController", new { id = Model.Id}))
{
for(int i = 0; i < Model.SomeCollection.Count(); i++)
{
#Html.HiddenFor(x => Model.SomeCollection.ElementAt(i).Id)
<div class="grid_6">
#Html.TextAreaFor(x => Model.SomeCollection.ElementAt(i).Text, new { #style = "height:150px", #class = "grid_6 input" })
</div>
}
<div class="grid_6 alpha omega">
<input type="submit" value="Next" class="grid_6 alpha omega button drop_4 gravity_5" />
</div>
}
On the Controller Side I have the following:
[HttpPost]
public ActionResult SomeAction(int id, SomeViewModel model)
{
return PartialView("_SomeOtherView", new SomeOtherViewModel(id));
}
My View Model is set up like this:
public class SomeViewModel
{
public SomeViewModel()
{
}
public IEnumerable<ItemViewModel> SomeCollection { get; set; }
}
public class ItemViewModel{
public ItemViewModel(){}
public int Id {get;set;}
public string Text{get;set;}
}
The SomeCollection is always empty when SomeAction if performed. What do I have to do in order to show the updated values by users. Text Property and Id field.
Use an EditorTemplate
Create an EditorTemplate folder under your Views/YourcontrollerName and create a view with name ItemViewModel.cshtml
And Have this code in that file
#model Project.Models.ViewModels.ItemViewModel
<p>
#Html.EditorFor(x => x.Text)
#Html.HiddenFor(x=>x.Id)
</p>
Now from your Main view, call it like this
#model Project.Models.ViewModels.SomeViewModel
#using (Html.BeginForm("SomeAction", "Home", new { id = Model.Id}))
{
#Html.EditorFor(s=>s.SomeCollection)
<div class="grid_6 alpha omega">
<input type="submit" value="Next" class="grid_6 alpha omega button drop_4 gravity_5" />
</div>
}
Now in your HTTPPOST method will be filled with values.
I am not sure what you want to do with the values( returning the partial view ?) So not making any comments about that.
I am not sure you have posted all the code.
Your action method does not do anything, since it returns a partial view (for some reason from a post call, not an ajax request) using a new model object.
Your effectively passing a model back to the action and then discarding it, and returning a new model object. This is the reason your collection is always empty, its never set anywhere.
Well, for one thing, why do you have both the model AND id, a property of model, sent back to the controller? Doesn't that seem a bit redundant? Also, you're using a javascript for loop in the view. It'd be much easier to just use #foreach.
Anyway, your problem is that when you tell an action to accept a model, it looks in the post for values with keys matching the names of each of the properties of the model. So, lets say we have following model:
public class Employee
{
public string Name;
public int ID;
public string Position;
}
and if I'm passing it back like this:
#using(Html.BeginForm("SomeAction", "SomeController"))
{
<input type="text" name = "name" [...] /> //in your case HtmlHelper is doing this for you, but same thing
<input type="number" name = "id" [...] />
<input type="submit" name = "position" [...] />
}
To pass this model back to a controller, I'd have to do this:
Accepting a Model
//MVC matches attribute names to form values
public ActionResult SomethingPosted(Employee emp)
{
//
}
Accepting a collection of values
//MVC matches parameter names to form values
public ActionResult SomethingPosted(string name, int id, string postion)
{
//
}
or this:
Accepting a FormCollection
//same thing as first one, but without a strongly-typed model
public ActionResult SomethingPosted(FormCollection empValues)
{
//
}
So, here's a better version of your code.
Your new view
#model Project.Models.ViewModels.SomeViewModel
#{
using (Html.BeginForm("SomeAction", "SomeController", new { id = Model.Id}))
{
foreach(var item in Model)
{
#Html.HiddenFor(item.Id)
<div class="grid_6">
#Html.TextAreaFor(item.Text, new { #style = "height:150px", #class = "grid_6 input" })
</div>
}
<div class="grid_6 alpha omega">
<input type="submit" value="Next" class="grid_6 alpha omega button drop_4 gravity_5" />
</div>
}
}
Your new action
[HttpPost]
public ActionResult SomeAction(int Id, string Text)
{
//do stuff with id and text
return PartialView("_SomeOtherView", new SomeOtherViewModel(id));
}
or
[HttpPost]
public ActionResult SomeAction(IEnumerable<ItemViewModel> SomeCollection) //can't use someviewmodel, because it doesn't (directly) *have* members called "Id" and "Text"
{
//do stuff with id and text
return PartialView("_SomeOtherView", new SomeOtherViewModel(id));
}
using the JQuery sortable, and trying to send the new order back to my controller, but not having a whole lot of luck. My view is:
using (Ajax.BeginForm("EditTickerOrder", new AjaxOptions { InsertionMode = InsertionMode.Replace, HttpMethod = "POST", }))
{
<div id="editableticker">
#Html.HiddenFor(m => m.ProjectGUID)
<ul id="sortablediv">
#foreach (DGI.CoBRA.Tools.BussinessObjects.CollabLibrary.TickerObjects.Ticker t in Model)
{
<li class="ui-state-default" id="#t.pKeyGuid.ToString()">
<p>#Html.CheckBox(t.pKeyGuid.ToString(), t.Display, new { #class = "activechk" })
<span style="font-weight: bold">
#t.Text
</span>
</p>
</li>
}
</ul>
<input type="submit" value="Save New Ticker Order" />
}
and my controller is:
[HttpPost]
public ActionResult EditTickerOrder(Guid ProjectGUID, List<string> items)
{
TickerCollectionModel TickerData = new TickerCollectionModel();
TickerData.ProjectGUID = ProjectGUID;
TickerData.ListAllBySession(ProjectGUID);
return PartialView("TickerList", TickerData);
}
yet the list<string> items is always null. Any ideas?
You are writing foreach loops, most definitely violating the naming conventions for your form input fields that the default model binder expects for working with collections. If you don't respect the established wire format, you cannot expect the default model binder to be able to rehydrate your models in the POST action.
In fact, why don't you use view models and editor templates? They make everything trivial in ASP.NET MVC.
So let's define a view model that will reflect your view requirements (or at least those shown in your question => you could of course enrich it with additional properties that you want to handle):
public class TickerViewModel
{
public Guid Id { get; set; }
public bool IsDisplay { get; set; }
public string Text { get; set; }
}
public class ProjectViewModel
{
public Guid ProjectGUID { get; set; }
public IEnumerable<TickerViewModel> Tickers { get; set; }
}
and then a controller whose responsibility is to query your DAL layer, retrieve a domain model, map the domain model into the view model we defined for this view and pass the view model to the view. Inversely, the POST action receives a view model from the view, maps the view model back into some domain model, passes the domain model to your DAL layer for processing and renders some view or redirects to a success action:
public class HomeController : Controller
{
public ActionResult Index()
{
// TODO: those values come from a data layer of course
var model = new ProjectViewModel
{
ProjectGUID = Guid.NewGuid(),
Tickers = new[]
{
new TickerViewModel { Id = Guid.NewGuid(), Text = "ticker 1" },
new TickerViewModel { Id = Guid.NewGuid(), Text = "ticker 2" },
new TickerViewModel { Id = Guid.NewGuid(), Text = "ticker 3" },
}
};
return View(model);
}
[HttpPost]
public ActionResult Index(ProjectViewModel model)
{
// Everything will be correctly bound here => map the view model
// back into your domain model and pass the domain model to
// your DAL layer for processing ...
return Content("Thanks for submitting");
}
}
a view (it is worth noting that in this example I have used a standard form instead of AJAX but it is trivial to convert it into an AJAX form):
#model ProjectViewModel
#using (Html.BeginForm())
{
#Html.HiddenFor(m => m.ProjectGUID)
<div id="editableticker">
<ul id="sortablediv">
#Html.EditorFor(x => x.Tickers)
</ul>
</div>
<button type="submit">OK</button>
}
and finally the corresponding editor template which will automatically be rendered for each element of the Tickers collection (~/Views/Home/EditorTemplates/TickerViewModel.cshtml):
#model TickerViewModel
<li class="ui-state-default">
<p>
#Html.CheckBoxFor(x => x.IsDisplay, new { #class = "activechk" })
#Html.LabelFor(x => x.IsDisplay, Model.Text)
#Html.HiddenFor(x => x.Text)
#Html.HiddenFor(x => x.Id)
</p>
</li>
I have the below code in my VIEW, and thereafter a submit button. I do have many of these checkboxes in my view, so that the user can click on as many as he wishes.
#Html.CheckBox("code" + l_code, false, new { Value = #item.expertiseCode })
In my controller i have the fll., which is the HTTPPost method
public ActionResult RegisterSP(RegisterModel model, FormCollection collection)
However, when debugging, i see that ALL the checkboxes are being passed back to the controller, and not just the ones that were clicked on. I just want the ones that were clicked on and ignore the rest for i need to add these to the DB. Also, the checbox values passed in contains TRUE/FALSE. Because of this the false value is also being added to the DB. If i use the below method (not using the htmlHelper), i dont have the above problem. But i wud like to use the htmlHelper:
<input type="checkbox" name="code#(l_code)" value="#item.expertiseCode" />
IF you have a collection of Checkboxes, Create a ViewModel like this
public class ExpertiseCodeViewModel
{
public string Name { set;get;}
public int ExpertiseId { set;get;}
public bool IsSelected { set;get;}
}
Now In your main ViewModel, Add a collection of this as a property
public class UserViewModel
{
public List<ExpertiseCodeViewModel > Expertises{ set; get; }
public UserViewModel()
{
if(this.Expertises==null)
this.Expertises=new List<ExpertiseCodeViewModel>();
}
}
And in your create an editor template called ExpertiseCodeViewModel
#model ExpertiseCodeViewModel
#Html.CheckBoxFor(x => x.IsSelected)
#Html.LabelFor(x => x.IsSelected, Model.Name)
#Html.HiddenFor(x => x.ExpertiseId )
Include this in your Main View
#model UserViewModel
#using (Html.BeginForm())
{
//other elements
#Html.EditorFor(m=>m.Expertises)
<input type="submit" value="Save" />
}
In your HTTPPost Action method,
[HttpPost]
public ActionResult Save(UserViewModel model)
{
List<int> items=new List<int>();
foreach (ExpertiseCodeViewModel objItem in model.Expertises)
{
if (objPVM.IsSelected)
{
//you can get the selected item id here
items.Add(objItem.ExpertiseId);
}
}
}
Try
#Html.CheckBox("code" + l_code, false, new { #value = item.expertiseCode })
or
string name = "code" + l_code;
#Html.CheckBox(name, false, new { #value = item.expertiseCode })
I'm sure this is easy, but maybe I haven't searched well ...
I want to know how to get results from a partial view back to the model and/or controller.
If the user enters a FirstName, Gender (from drop down) and Grade (from drop down), I only find then FirstName and Gender in the model. I want to know how to get the Grade from the drop down in the partial view all the way back into the model, so I can see it in the controller.
Please look for this question in the controller code:
What do I need to do to get the GradeLevel from the partial class to be here: <<<<<
Note: this is not the exact code. There may be small, insignificant typo's.
EDIT: Apparently you can't add a long comment, so I will add here:
Thank you, Tom and Mystere Man. Tom got me thinking as to why it doesn't work. I didn't think through the model binding. With the design I proposed, the HTML gets rendered and the Grade drop down has this id: "Grade". The property on the model I want to bind to is: "GradeLevelID". If I change the helper in the partial view to be #Html.DropDownList("GradeLevelID" ... it works perfectly.
But that is not a good solution. My idea was to abstract the partial view from the main view. Hard coding the name blows that! I did work up a slightly improved solution. In the main view, I change the #Html.Partial statement to pass the model property name to the partial. Like such:
#Html.Partial("GradeDropDown", (SelectList)Model.GradeSelectList, new ViewDataDictionary { { "modelPropertyName", "GradeLevelID" } })
Then I could change the partial view to say
#model System.Web.Mvc.SelectList
#Html.DropDownList((string)ViewData["modelPropertyName"], Model)
But that also seems like a goofy way to approach things. Thanks for the help. I'll look at EditorTemplates.
Here is my model:
public class RegisterModel{
public MemberRegistration MemberRegistration{
get{
if (HttpContext.Current.Session["MemberRegistration"] == null){
return null;
}
return (MemberRegistration)HttpContext.Current.Session["MemberRegistration"];
}
set{
HttpContext.Current.Session["MemberRegistration"] = value;
}
}
public string FirstName{
get{
return MemberRegistration.FirstName;
}
set{
MemberRegistration.FirstName = value;
}
}
public SelectList GenderSelectList{
get{
List<object> tempList = new List<object>();
tempList.Add(new { Value = "", Text = "" });
tempList.Add(new { Value = "M", Text = "Male" });
tempList.Add(new { Value = "F", Text = "Female" });
return new SelectList(tempList, "value", "text", MemberRegistration.Gender);
}
}
[Required(ErrorMessage = "Gender is required")]
public string Gender{
get{
return MemberRegistration.MemberPerson.Gender;
}
set{
MemberRegistration.MemberPerson.Gender = value;
}
}
public SelectList GradeLevelSelectList{
get{
List<object> tempList = new List<object>();
tempList.Add(new { Value = "", Text = "" });
tempList.Add(new { Value = "1", Text = "1st" });
tempList.Add(new { Value = "2", Text = "2nd" });
tempList.Add(new { Value = "3", Text = "3rd" });
tempList.Add(new { Value = "4", Text = "4th" });
return new SelectList(tempList, "value", "text", MemberRegistration.GradeLevel);
}
}
[Required(ErrorMessage = "Grade is required")]
public Int32 GradeLevel{
get{
return MemberRegistration.GradeLevel;
}
set{
MemberRegistration.GradeLevel = value;
}
}
}
Here is my main view:
#model RegisterModel
#using (Html.BeginForm())
{
<p class="DataPrompt">
<span class="BasicLabel">First Name:</span>
<br />
#Html.EditorFor(x => x.FirstName)
</p>
<p class="DataPrompt">
<span class="BasicLabel">Gender:</span>
<br />
#Html.DropDownListFor(x => x.Gender, Model.GenderSelectList)
</p>
<p class="DataPrompt">
<span class="BasicLabel">Grade:</span><span class="Required">*</span>
<br />
#Html.Partial("GradeDropDown", (SelectList)Model.GradeLevelSelectList)
</p>
<p class="DataPrompt">
<input type="submit" name="button" value="Next" />
</p>
}
Here is my partial view (named "GradeDropDown"):
#model System.Web.Mvc.SelectList
#Html.DropDownList("Grade", Model)
Here is my controller:
[HttpPost]
public ActionResult PlayerInfo(RegisterModel model)
{
string FirstName = model.Registration.FirstName;
string Gender = model.Registration.Gender;
>>>>> What do I need to do to get the GradeLevel from the partial class to be here: <<<<<
Int32 GradeLevel = model.Registration.GradeLevel;
return RedirectToAction("Waivers");
}
I don't even know why you are using a partial view. All you're doing is using one helper method, you could replace the partial view with the helper method in the view and it would be less code.
Second, you should be using Html.DropDownListFor() instead of Html.DropDownList(), then it will correctly name the html controls for you.
Just do this:
<p class="DataPrompt">
<span class="BasicLabel">Grade:</span><span class="Required">*</span>
<br />
#Html.DropDownListFor(m => m.GradeLevel, (SelectList)Model.GradeLevelSelectList)
</p>
try this to get the correct naming for the elements when they get posted.
On your main view
#Html.Partial("GradeDropDown", Model) //Pass the Model to the partial view
Here is your partial view (named "GradeDropDown"):
#model RegisterModel
#Html.DropDownList("Grade", (SelectList)Model.GradeLevelSelectList)