Html DropdownListFor selected value not being set

Question

How can I set the selected value of a Html DropDownListFor  I ve been having a look online and have seen that it can be achieved by using the fourth parameter so like the below    Html DropDownListFor m   gt  m  new SelectList Model   Code    Name   0     Please select a country     My select list then display like this    lt select id  ShipFromCountries  name  ShipFromCountries  gt        lt option value    gt Please select a country lt  option gt        lt option value  GB  gt United Kingdom lt  option gt        lt option value  US  gt United States lt  option gt            lt  select gt    But for some reason United Kingdom remains selected but I want  Please select a country  to be selected    Anyone know how I can achieve this   EDIT  I ve updated my code as there was a slight change in functionality however still seem to be encountering this problem  This is what is in my view    Html DropDownListFor n   gt  n OrderTemplates  new SelectList Model OrderTemplates   OrderTemplateId    OrderTemplateName   1    Please select an order template     1 is the Id of the option that I want selected  I have also tried with the text of the option but that also does not work   Any ideas

User · Answer

Add the Controller Section    ViewBag Orders  new SelectList db Orders   Id    business   paramid     Add the Html Section      Html DropDownList  Orders   null    A simple method

User · Answer

For me was not working so worked this way   Controller   int selectedId   1   ViewBag ItemsSelect   new SelectList db Items   ItemId    ItemName  selectedId     View    Html DropDownListFor m   gt  m ItemId  SelectList ViewBag ItemsSelect    JQuery      document   ready function              ItemId   val   Model ItemId

User · Answer

This is CSS issues  I don t know why   Html DropDownListFor in Bootstrap 4 doest work  Surely this is class design problem  Anyways the work arround is  if your Dropdown input box has CSS Padding   px    px  element then disable it  Hope this will work

User · Answer

Linq to Dropdown with empty item  selected item  works 100    Strongly Typed Chances for error minimum  Any model changes will be reflected in the binding  Controller  public ActionResult ManageSurveyGroup                 tbl Survey sur   new tbl Survey            sur Survey Est    3            return View sur           View                      Step One   Getting all the list     var CompEstdList    from ComType in db tbl CompEstdt orderby ComType Comp EstdYr select ComType  ToList           Step Two    Adding a no Value item        CompEstdList Insert 0  new eDurar Models tbl CompEstdt   Comp Estdid   0  Comp EstdYr    --Select Company Type--             Step Three   Setting selected Value if value is present     var selListEstd  CompEstdList Select s   gt  new SelectListItem   Text   s Comp EstdYr  Value   s Comp Estdid ToString                           Html DropDownListFor model   gt  model Survey Est  selListEstd           Html ValidationMessageFor model   gt  model Survey Est    This method for binding data also possible  var selList   CompTypeList Select s   gt  new SelectListItem   Text   s CompTyp Name  Value   s CompTyp Id ToString    Selected   s CompTyp Id    3   true   false

User · Answer

If you know what will be in the view  you can also set the default value from Controller as well rather then set up it into the view cshtml file  No need to set default value from HTML side   In the Controller file   commission TypeofCommission   1  return View commission     In the  cshtml file    Html DropDownListFor row   gt  row TypeofCommission  new SelectList Model commissionTypeModelList   type    typeName     --Select--

User · Answer

I had a similar issue  I was using the ViewBag and Element name as same   Typing mistake

User · Answer

When you pass an object like this   new SelectList Model   Code    Name   0    you are saying  the Source  Model  and Key   Code   the Text   Name   and the selected value 0  You probably do not have a 0 value in your source for Code property  so the HTML Helper will select the first element to pass the real selectedValue to this control

User · Answer

Make sure that you have trim the selected value before you assigning     Model  public class SelectType       public string Text   get  set        public string Value   get  set          Controller  var types   new List lt SelectType gt     types Add new SelectType     Value    0  Text    Select a Type      types Add new SelectType     Value    1  Text    Family Trust      types Add new SelectType     Value    2  Text    Unit Trust     ViewBag PartialTypes   types      View   Html DropDownListFor m   gt  m PartialType  new SelectList ViewBag PartialTypes   Value    Text    new   id    Type

User · Answer

public byte UserType public string SelectUserType   You need to get one and set different one  Selected value can not be the same item that you are about to set    Html DropDownListFor p   gt  p SelectUserType  new SelectList   UserTypeNames   Key    Value  UserType     I use Enum dictionary for my list  that s why there is  key    value  pair

User · Answer

You should forget the class     SelectList   Use this in your Controller   var customerTypes   new           new SelectListItem   Value    all   Text   All        new SelectListItem   Value    business   Text   Business        new SelectListItem   Value    private   Text   Private         Select the value   var selectedCustomerType   customerTypes FirstOrDefault d   gt  d Value     private    if  selectedCustomerType    null      selectedCustomerType Selected   true    Add the list to the ViewData   ViewBag CustomerTypes   customerTypes    Use this in your View    Html DropDownList  SectionType    SelectListItem   ViewBag CustomerTypes    -  More information at  http   www asp net mvc overview older-versions working-with-the-dropdownlist-box-and-jquery using-the-dropdownlist-helper-with-aspnet-mvc

User · Answer

I know this is not really an answer to the question  but I was looking for a way to initialize the DropDownList from a list on the fly in the view when I kept stumbling upon this post    My mistake was that I tried to create a SelectList from dictionary like this     wrong   Html DropDownListFor m   gt  m Locality  new SelectList new Dictionary lt string  string gt        Model Locality  Model Locality text      Model Locality        I then went digging in the official msdn doc  and found that DropDownListFor doesn t necessarily require a SelectList  but rather an IEnumerable lt SelectListItem gt      right  Html DropDownListFor m   gt  m Locality  new List lt SelectListItem gt      new SelectListItem     Value   Model Locality  Text   Model Locality text  Selected   true      Model Locality  new    class    form-control select2ddl       In my case I can probably also omit the Model Locality as selected item  since its a  the only item and b  it already says it in the SelectListItem Selected property   Just in case you re wondering  the datasource is an AJAX page  that gets dynamically loaded using the SelectWoo Select2 control

User · Answer

For me general solution             var selectedCity   Model Cities Where k   gt  k Id    Model Addres CityId  FirstOrDefault         if  selectedCity    null                    Html DropDownListFor model   gt  model Addres CityId  new SelectList Model Cities   Id    Name   selectedCity Id   new    class    form-control                 else                   Html DropDownListFor model   gt  model Cities  new SelectList Model Cities   Id    Name    1    new    class    form-control

User · Answer

Your code has some conceptual issues   First    Html DropDownListFor n   gt  n OrderTemplates  new SelectList Model OrderTemplates   OrderTemplateId    OrderTemplateName   1    Please select an order template     When using DropDownListFor  the first parameter is the property where your selected value is stored once you submit the form   So  in your case  you should have a SelectedOrderId as part of your model or something like that  in order to use it in this way     Html DropDownListFor n   gt  n SelectedOrderId  new SelectList Model OrderTemplates   OrderTemplateId    OrderTemplateName   1    Please select an order template     Second   Aside from using ViewBag  that is not wrong but there are better ways  put that information in the ViewModel instead   there is a  little bug   or an unspected behavior  when your ViewBag property  where you are holding the SelectList  is the same name of the property where you put the selected value  To avoid this  just use another name when naming the property holding the list of items   Some code I would use if I were you to avoid this issues and write better MVC code   Viewmodel   public class MyViewModel     public int SelectedOrderId  get  set      public SelectList OrderTemplates  get  set          Other properties you need in your view     Controller   public ActionResult MyAction       var model   new MyViewModel       model OrderTemplates   new SelectList db OrderTemplates   OrderTemplateId    OrderTemplateName   1        Other initialization code     return View model       In your View    Html DropDownListFor n   gt  n SelectedOrderId  Model OrderTemplates   Please select an order template

[asp.net-mvc] Html.DropdownListFor selected value not being set

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