I am using a dropdown list as follows.
<%=Html.DropDownList("ddl", ViewData["Available"] as SelectList,
new { CssClass = "input-config", onchange = "this.form.submit();" })%>
On its selection change I am invoking post action. After the post the same page is shown on which this drop down is present. I want to know about the HTML attribute for the drop down which will let me preserve the list selection change. But as of now the list shows its first element after the post.
e.g. The dropdoen contains elements like 1,2,3,etc. By default 1 is selected. If I select 2, the post is invoked and the same page is shown again but my selection 2 goes and 1 is selected again.
How can preserve the selection?
Thanks,
Kapil
You have to make the list of select list items again and tell which of the items is the selected one in every post (Selected property of the SelectListItem).
When you perform the post you will be setting the ViewData["Available"] again, you can set the select item here. So when you create the drop down list in the html the selected item is already selected. So your code could look something like:
ViewData["Available"] = new SelectList( items, "dataValueField", "dataTextField", "selectedValue" );
You have to take the property model ddl, or receive it as a parameter in the action, such as:
public ActionResult Action(Model model, string ddl)
Then to create ViewData [" Available "], you have to pass it as selected value
public ActionResult Action(Model model, string ddl)
{
ViewData["Available"] = List<SelectListItem>
{
new SelectListItem { Text = "1", Value = "1", Selected = (ddl == "1") },
new SelectListItem { Text = "2", Value = "2", Selected = (ddl == "2") },
new SelectListItem { Text = "3", Value = "3", Selected = (ddl == "3") }
};
return View(model);
}
OR:
public ActionResult Action(Model model, string ddl)
{
var list = List<SelectListItem>
{
new SelectListItem { Text = "1", Value = "1" },
new SelectListItem { Text = "2", Value = "2" },
new SelectListItem { Text = "3", Value = "3" }
};
ViewData["ddl"] = new SelectList(list, "value", "text", ddl);
return View(model);
}
EDIT: See also this
This worked for me:
<%=Html.DropDownList("Ibus", ViewData["Ibus"] as SelectList, new { **#class** = "dASDropDown" })%>
Related
I am trying to use Html.DropDownListFor with the list of strings from a ViewBag.
Basically I got a ViewBag with a list of string like "Adam","Tom","Mike" etc...
I was wandering if it is possible to pass this list in to DropDownListFor where both Value and text are the items from my list.
I wasn't able to use foreach here...
example with hardcode:
#Html.DropDownListFor(model => model.Name, new SelectList(
new List<Object>{
new { value = "Adam" , text = "Adam" },
new { value = "Tom" , text = "Tom" },
new { value = "Mike" , text = "Mike" },
new { value = "Jake" , text = "Jake" },
},
"value",
"text",
2))
You can generate a collection of SelectListItems from the list of strings and use that with DropDownListFor helper method.
var names = new List<string> {"Adam", "Sam"};
ViewBag.Names = names.Select(f => new SelectListItem() {Value = f, Text = f});
and in the view
#Html.DropDownListFor(f=>f.Name, ViewBag.Names as IEnumerable<SelectListItem>,
"select one")
I need to pass the value of a Kendo drop-down list to the action method within a controller from a Html.RenderAction helper. I can't for the life of me recall how to do this. How do I pass the selected value to the controller? This would be the same method you would use for a normal drop-down list.
// Drop-down list
#(Html.Kendo().DropDownList()
.Name("dropDownList")
.DataTextField("Text")
.DataValueField("Value")
.OptionLabel("Please select")
.BindTo(new List<SelectListItem>
{
new SelectListItem
{
Text = "Test 1",
Value = "1"
},
new SelectListItem
{
Text = "Test 2",
Value = "2"
},
new SelectListItem
{
Text = "Test 3",
Value = "3"
}
}))
// RenderAction
#{Html.RenderAction("DoSomething", new { value = %dropDownListSelectedValue% }); }
// Controller
public ActionResult DoSomething(string value)
{
...
}
I have an action that retrieves data and sends it to a view. In a view I have two dropdown menus.
First drop down shows salutation (such as "Mr.", "Ms.", etc.) and does not select value I sent for some reason. The other dropdown shows language list and correctly selects value I sent to the view. The relevant code in view is shown below.
#Html.DropDownListFor(model => model.Salutation, ViewBag.salutation as IEnumerable<SelectListItem>)
#Html.DropDownListFor(model => model.Language, ViewBag.languages as IEnumerable<SelectListItem>)
In the controller I have the following code to get the dropdown data.
ViewBag.salutation = new List<SelectListItem>() {
new SelectListItem() { Text = "", Value = "" },
new SelectListItem() { Text = "Mr.", Value = "Mr." },
new SelectListItem() { Text = "Ms.", Value = "Ms." },
new SelectListItem() { Text = "Mrs.", Value = "Mrs." }
};
and
var languages = (from l in db.Languages.ToList()
select new SelectListItem()
{
Text = l.Language,
Value = l.LanguageId.ToString()
}).ToList();
languages.Insert(0, new SelectListItem() { Text = "", Value = "" });
ViewBag.languages = languages;
The only difference I could think of is that the languages dropdown has an integer as value, whereas salutation dropdown has text as value. Is this why the salutation dropdown doesn't work? I know I could go through each salutation List<SelectListItem> item and set Selected property based on the value I retrieved from database. But I was hoping there would be a cleaner way to do this.
Any ideas?
Thanks
UPDATE
I decided to do what I did for another project.
IList<SelectListItem> _salutation = new List<SelectListItem>()
{
new SelectListItem() { Value = "", Text = "" },
new SelectListItem() { Value = "Mr.", Text = "Mr." },
new SelectListItem() { Value = "Ms.", Text = "Ms." },
new SelectListItem() { Value = "Mrs.", Text = "Mrs." }
};
// I could put the following in the declaration above, but for testing purposes it's in foreach loop.
foreach (var item in _salutation)
{
// compare to what's retrieved from database
item.Selected = item.Value == _viewData.Salutation;
}
ViewBag.salutation = _salutation;
After foreach loop I output .Value, .Selected property of each item in _salutation and I get all the correct values with one item being selected. Inside the view I did the following.
#foreach (var item in ViewBag.salutation as IEnumerable<SelectListItem>)
{
<b>#item.Value : #item.Text : #item.Selected</b><br />
}
All the correct Text/Values come up but none are Selected! This happens if I output the values after I execute #Html.DropDownListFor(). If I output the ViewBag.salutation before the html helper the correct value is selected.
SOLUTION
I found the following article useful: DropDownListFor with ASP.NET MVC.
Instead of using ViewBag I added the following to the ViewModel. (Showing the part for salutations drop down.)
public class TheViewModel
{
private IList<string> _salutations = new List<string>() { "", "Mr.", "Ms.", "Mrs." };
public IEnumerable<SelectListItem> SalutationItems
{
get
{
var salutations = _salutations.Select(s => new SelectListItem { Value = s, Text= s });
return salutations;
}
}
// The rest of the ViewModel
}
And in the View I have the following.
#Html.DropDownListFor(model => model.Salutation, Model.SalutationItems)
Instead of just supplying the list to the DropDownListFor helper you could provide it a SelectList. The SelectList constructor takes the list and allows you to explicitly set the selected value as well as an overload that lets you specify the Text and Value fields.
#Html.DropDownListFor(model => model.Salutation,
new SelectList(ViewBag.salutation as IEnumerable<SelectListItem>,
"Value", "Text", Model.Salutation))
Try this,
#Html.DropDownListFor(m =>m.DDCountryModel,IEnumerable<SelectListItem>)ViewBag.salutation)
#Html.DropDownListFor(model => model.Language, IEnumerable<SelectListItem>)ViewBag.languages)
Your Model should be like this,
public class Model
{
public IEnumerable<SelectListItem> DDCountryModel{ get; set; }
public IEnumerable<SelectListItem> Language{ get; set; }
}
I can create a dropdown list with items from the ViewBag, but there doesn't seem to be a way to select the current item. I'm not using the model to achieve this, just want to use ViewBag, otherwise I'd have to create another model class just to wrap the select items and the actual data to display.
My code:
#Html.DropDownList("MyFilter", (IEnumerable<SelectListItem>)ViewBag.SelectItems, "Show All" )
There is no parameter to set the value of the select list. Am I overlooking something?
If I were to use DropDownListFor<> does this only work against the model?
You could try setting the MyFilter property in your ViewBag/ViewData:
public ActionResult Index()
{
ViewBag.SelectItems = new[]
{
new SelectListItem { Value = "1", Text = "item 1" },
new SelectListItem { Value = "2", Text = "item 2" },
new SelectListItem { Value = "3", Text = "item 3" },
};
// preselect the second item
ViewBag.MyFilter = "2";
return View();
}
But my recommendation is to use view models and the strongly typed version of the helper:
public ActionResult Index()
{
var model = new MyViewModel
{
SelectItems = new[]
{
new SelectListItem { Value = "1", Text = "item 1" },
new SelectListItem { Value = "2", Text = "item 2" },
new SelectListItem { Value = "3", Text = "item 3" },
},
// preselect the second item
MyFilter = "2"
};
return View(model);
}
and in your strongly typed view:
#model MyViewModel
...
#Html.DropDownListFor(x => x.MyFilter, Model.SelectItems, "Show all")
I am using the following to generate a drop down list:
#for (var index = 0; index < Model.AdminSummaries.Count(); index++)
{
<div class="rep_tr0">
<div class="rep_td0">
#Html.DropDownListFor(x => Model.AdminSummaries[index].Status,
AdminStatusReference.GetAdminStatusOptions(),
new { id = string.Format("Status_{0}",index ) })
</div>
</div>
}
Here's the HTML it generates:
<select id="Status_1" name="AdminSummaries[1].Status"><option value="1">Released</option>
<option value="2">Review</option>
<option value="3">New</option>
</select>
Here's the class that gives the status options.
public static class AdminStatusReference
{
public static IEnumerable<SelectListItem> GetAdminStatusOptions()
{
return new[]
{
new SelectListItem { Value = "1", Text = "Released" },
new SelectListItem { Value = "2", Text = "Review" },
new SelectListItem { Value = "3", Text = "New" }
};
}
}
Everything works good EXCEPT it doesn't select the items correctly. There's no option with 'selected' to match the data in the AdminSummaries.
How can I make it so the correct select list items are selected?
Just to clarify this. My problem is that if there is a data record with a value of 3 for the status then when I look at the screen I see a select list with the word "Release" showing.
What I need is for the select list to show text that corresponds with the data value.
Here is the more accurate answer
public static class AdminStatusReference
{
public static IEnumerable<SelectListItem> GetAdminStatusOptionsFor(AdminSummaries arg)
{
var options = new[]
{
new SelectListItem { Value = "1", Text = "Released" },
new SelectListItem { Value = "2", Text = "Review" },
new SelectListItem { Value = "3", Text = "New" }
};
options.First(o=> o.Value == arg).Selected = true;
return options;
}
}
Set the SelectListItem.Selected property to true:
public static class AdminStatusReference
{
public static IEnumerable<SelectListItem> GetAdminStatusOptions()
{
return new[]
{
new SelectListItem { Value = "1", Text = "Released", Selected = true },
new SelectListItem { Value = "2", Text = "Review" },
new SelectListItem { Value = "3", Text = "New" }
};
}
}
It seams from the source code that the DropDownListFor method (actually the ViewDataEvaluator.Eval method) doesn't support expressions containing indexers. Because your expression: AdminSummaries[index].Status contains an indexer that's why the framework doesn't use the selected value from your model class.
The only solution is to specify the selected item when setting the SelectListItem collection, you can do this by passing the currently selected value to your GetAdminStatusOptions method:
View:
#Html.DropDownListFor(x => Model.AdminSummaries[index].Status,
AdminStatusReference.GetAdminStatusOptions(Model.AdminSummaries[index].Status),
new { id = string.Format("Status_{0}",index ) })
A sample GetAdminStatusOptions implementation:
public static IEnumerable<SelectListItem> GetAdminStatusOptions(string selected = null)
{
var options = new[]
{
new SelectListItem {Value = "1", Text = "Released"},
new SelectListItem {Value = "2", Text = "Review"},
new SelectListItem {Value = "3", Text = "New"}
};
foreach (var option in options)
{
option.Selected = option.Value == selected;
}
return options;
}