如何根据MVC中数据库的值选择默认值 [英] How to get default value selected based on value from database in MVC

问题描述

我在数据库中有一个表，用于存储用户注册时用户的所有值。我想在编辑模式下在表单中检索这些值。我已成功获取列表中的所有值，并在表单的编辑模式下在文本框中可见。但是表格中也有一个下拉列表，我无法根据来自目前列表中的数据库的值来设置下拉列表的默认值。



DataLayer

  public 列表< registerviewmodel> GetUserdetail（ string 角色）
 {
 尝试 
 {
 cmd =  new  SqlCommand（）; 
 RegisterViewModel mvm; 
 List< registerviewmodel> lstMVM =  new  List< registerviewmodel>（）; 
 cmd.CommandText =   getUserdetail; 
  if （！String.IsNullOrEmpty（Role））
 {
 cmd.Parameters.Add（  @ Role，SqlDbType.NVarChar）.Value = Role; 
} 
 DataTable dtModel = dl.GetSpData（cmd）; 
  foreach （DataRow dr  in  dtModel.Rows）
 {
 mvm =  new  RegisterViewModel（）; 
 mvm.Id = dr [  Id]。ToString（）; 
 mvm.CustomerName = dr [ 客户名称]。ToString（）; 
 mvm.Company = dr [  Company]。ToString（）; 
 mvm.Address = dr [  Address]。ToString（）; 
 mvm.City = dr [  City]。ToString（）; 
 mvm.RegionAbri = dr [  Region]。ToString（）; 
 mvm.PostalCode = dr [ 邮政编码]。ToString（）; 
 mvm.CountryId =  int  .Parse（dr [  CountryId]的ToString（））; 
 mvm.CountryName = dr [  CountryName]。ToString（）; 
 mvm.PhoneNumber = dr [ 电话号码]。ToString（）; 
 mvm.Fax = dr [  Fax]。ToString（）; 
 mvm.Email = dr [  Email]。ToString（）; 
 mvm.AckEmail = dr [  AckEmail]。ToString（）; 
 mvm.ApplicationDate = dr [ 申请日期]。ToString（）; 
 mvm.UserVerified = dr [  User Verified]。ToString（）; 
 mvm.UserStatus = dr [ 用户状态]。ToString（）; 
 mvm.CustomerNo = dr [  CustomerNo]。ToString（）; 
 mvm.Password = dr [  PasswordHash]。ToString（）; 
 mvm.Multiplier = dr [ 乘数]。ToString（）; 
 mvm.QuoteExpire = dr [  QuoteExpire]。ToString（）; 
 mvm.Freight = dr [  Freight]。ToString（）; 
 mvm.Rep = dr [  Rep]。ToString（）; 
 mvm.ISENumber = dr [  ISENumber]。ToString（）; 
 mvm.ReceiveMail = dr [  ReceiveMail]。ToString（）; 
 mvm.BuyingGroup = dr [  BuyingGroup]。ToString（）; 
 mvm.Comments = dr [  Comments]。ToString（）; 
 lstMVM.Add（mvm）; 
} 
  return  lstMVM; 
} 
  catch （例外e）
 {
  throw  e; 
 
} 
} 

控制器

  public  ActionResult UserMaintainance（）
 
 {
 eQuoteDataAccess eqda =  new  eQuoteDataAccess（）; 
 RegisterViewModel model =  new  RegisterViewModel（）; 
 model.UserList = eqda.GetUserdetail（Role）; 
  return 查看（模型）; 
} 
 

查看

 @ foreach（Model.UserList中的var项目） ）
 {@ Html.DropDownListFor（modelitem => item.CountryId，Model.Country）} <   / registerviewmodel  >  <   / registerviewmodel  >  <   / registerviewmodel  >  

解决方案

之后DataBind（）：



dropDown.SelectedIndex = 0;

或

dropDown.SelectedValue =anyValue;

或

dropDown.Items.FindByValue（anyValue）。Selected = true;

或

dropDown.Items.FindByText（anyValue）。Selected = true;



尝试以下任何一项，这可能会有效:)



-KR

I have a table in database which stores all the value about the user when the user registers.i want to retrive those values in the form in edit mode. i have successfully got all values in a list, and is getting visible in textbox in edit mode of the form. but there is a dropdown in the form too, i am not able to get how to set the default value of the dropdown based on my value coming from the databse which is presently in list.

DataLayer

public List<registerviewmodel> GetUserdetail(string Role)
        {
            try
            {
                cmd = new SqlCommand();
                RegisterViewModel mvm;
                List<registerviewmodel> lstMVM = new List<registerviewmodel>();
                cmd.CommandText = "getUserdetail";
                if (!String.IsNullOrEmpty(Role))
                {
                    cmd.Parameters.Add("@Role", SqlDbType.NVarChar).Value = Role;
                }
                DataTable dtModel = dl.GetSpData(cmd);
                foreach (DataRow dr in dtModel.Rows)
                {
                    mvm = new RegisterViewModel();
                    mvm.Id = dr["Id"].ToString();
                    mvm.CustomerName = dr["Customer Name"].ToString();
                    mvm.Company = dr["Company"].ToString();
                    mvm.Address = dr["Address"].ToString();
                    mvm.City = dr["City"].ToString();
                    mvm.RegionAbri = dr["Region"].ToString();
                    mvm.PostalCode = dr["Postal Code"].ToString();
                    mvm.CountryId = int.Parse(dr["CountryId"].ToString());
                    mvm.CountryName = dr["CountryName"].ToString();
                    mvm.PhoneNumber = dr["Phone Number"].ToString();
                    mvm.Fax = dr["Fax"].ToString();
                    mvm.Email = dr["Email"].ToString();
                    mvm.AckEmail = dr["AckEmail"].ToString();
                    mvm.ApplicationDate = dr["Application Date"].ToString();
                    mvm.UserVerified = dr["User Verified"].ToString();
                    mvm.UserStatus = dr["User Status"].ToString();
                    mvm.CustomerNo = dr["CustomerNo"].ToString();
                    mvm.Password = dr["PasswordHash"].ToString();
                    mvm.Multiplier = dr["Multiplier"].ToString();
                    mvm.QuoteExpire = dr["QuoteExpire"].ToString();
                    mvm.Freight = dr["Freight"].ToString();
                    mvm.Rep = dr["Rep"].ToString();
                    mvm.ISENumber = dr["ISENumber"].ToString();
                    mvm.ReceiveMail = dr["ReceiveMail"].ToString();
                    mvm.BuyingGroup = dr["BuyingGroup"].ToString();
                    mvm.Comments = dr["Comments"].ToString();
                    lstMVM.Add(mvm);
                }
                return lstMVM;
            }
            catch (Exception e)
            {
                throw e;

            }
        }

Controller

public ActionResult UserMaintainance()

       {
           eQuoteDataAccess eqda = new eQuoteDataAccess();
           RegisterViewModel model = new RegisterViewModel();
           model.UserList = eqda.GetUserdetail(Role);
           return View(model);
       }

View

@foreach (var item in Model.UserList)
{ @Html.DropDownListFor(modelitem => item.CountryId,Model.Country)}</registerviewmodel></registerviewmodel></registerviewmodel>

解决方案

After your DataBind():

dropDown.SelectedIndex = 0;
or
dropDown.SelectedValue = "anyValue";
or
dropDown.Items.FindByValue("anyValue").Selected = true;
or
dropDown.Items.FindByText("anyValue").Selected = true;

Try any of this, this might work :)

-KR

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