Example E4425

Visible to All Users

Grid View for ASP.NET MVC - How to implement cascading combo boxes in the grid's edit form

This example demonstrates how to create cascading combo box editors and use them to edit grid data.

Overview

Follow the steps below to implement cascading combo boxes in the grid's edit form:

Call a column's MVCxGridViewColumn.EditorProperties method to add a combo box editor to the column.

Razor
settings.Columns.Add(c => c.CountryId, country =>{  
     country.Caption = "Country";  
     country.EditorProperties().ComboBox(cs => cs.Assign(ComboBoxPropertiesProvider.Current.CountryComboBoxProperties));  
 });  
 settings.Columns.Add(c => c.CityId, city =>{  
     city.Caption = "City";  
     city.EditorProperties().ComboBox(cs => cs.Assign(ComboBoxPropertiesProvider.Current.CityComboBoxProperties));  
 });

Add a MVCxColumnComboBoxProperties object to specify an editor's settings and call the MVCxColumnComboBoxProperties.BindList method to bind the column to a data source.

C#
MVCxColumnComboBoxProperties countryComboBoxProperties;  
public MVCxColumnComboBoxProperties CountryComboBoxProperties {  
    get {  
        if(countryComboBoxProperties == null)  
            countryComboBoxProperties = CreateCountryComboBox();  
        return countryComboBoxProperties;  
    }  
}  
protected MVCxColumnComboBoxProperties CreateCountryComboBox() {  
    MVCxColumnComboBoxProperties cs = new MVCxColumnComboBoxProperties();  
    cs.CallbackRouteValues = new { Controller = "Home", Action = "ComboBoxCountryPartial" };  
    // ...  
    cs.ClientSideEvents.SelectedIndexChanged = "CountriesCombo_SelectedIndexChanged";  
    cs.BindList(WorldCities.Countries.ToList());  
    return cs;  
}

Specify the secondary editor's CallbackRouteValue parameters.

Handle the primary editor's SelectedIndexChanged event. In the handler, call the secondary editor's PerformCallback method to update the editor's data.

JavaScript
function CountriesCombo_SelectedIndexChanged(s, e) {  
    customCallback = true;  
    grid.GetEditor('CityId').PerformCallback();  
}

Handle the secondary editor's client-side BeginCallback event and pass the selected value of the secondary editor as a parameter.

JavaScript
function CitiesCombo_BeginCallback(s, e) {  
    e.customArgs['CountryId'] = grid.GetEditor('CountryId').GetValue();  
}

Use the grid's GetComboBoxCallbackResult method to get the result of callback processing.

C#
public ActionResult ComboBoxCountryPartial(){  
    return GridViewExtension.GetComboBoxCallbackResult(ComboBoxPropertiesProvider.Current.CountryComboBoxProperties);  
}

Call the secondary editor's CallbackRouteValues.Action method to populate the editor with values based on the passed parameter.

Files to Review

HomeController.cs (VB: HomeController.vb)
Global.asax (VB: Global.asax)
Global.asax.cs (VB: Global.asax.vb)
City.cs (VB: City.vb)
ComboBoxPropertiesProvider.cs (VB: ComboBoxPropertiesProvider.vb)
Country.cs (VB: Country.vb)
Customer.cs (VB: Customer.vb)
WoldCitiesModel.Context.cs (VB: WoldCitiesModel.Context.vb)
WoldCitiesModel.cs (VB: WoldCitiesModel.vb)
GridViewPartial.cshtml
Index.cshtml

Documentation

More Examples

ComboBox for ASP.NET MVC - How to implement cascading combo boxes

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Example Code

Controllers/HomeController.cs(vb)

C#
VB.NET

C#
using System;
using System.Web.Mvc;
using E4425.Models;
using DevExpress.Web.Mvc;
using System.Linq;
namespace E4425.Controllers
{
    public class HomeController : Controller
    {
        WorldCitiesEntities entity = new WorldCitiesEntities();
        public ActionResult Index()
        {
            return View(entity.Customers.ToList());
        }
        public ActionResult GridViewPartial()
        {
            return PartialView(entity.Customers.ToList());
        }
        public ActionResult GridViewEditPartial(Customer customerInfo)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    entity.Customers.Attach(customerInfo);
                    var entry = entity.Entry(customerInfo);
                    entry.Property(e => e.CityId).IsModified = true;
                    entry.Property(e => e.CountryId).IsModified = true;
                    entry.Property(e => e.CustomerName).IsModified = true;
                    // uncomment the next line to enable database updates
                    //   entity.SaveChanges();
                }
                catch (Exception e)
                {
                    ViewData["EditError"] = e.Message;
                }
            }
            else
                ViewData["EditError"] = "Please, correct all errors.";
            return PartialView("GridViewPartial", entity.Customers.ToList());
        }
        public ActionResult GridViewInsertPartial(Customer customerInfo)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    entity.Customers.Add(customerInfo);
                    // uncomment the next line to enable database updates
                    // entity.SaveChanges();
                }
                catch (Exception e)
                {
                    ViewData["EditError"] = e.Message;
                }
            }
            else
                ViewData["EditError"] = "Please, correct all errors.";
            return PartialView("GridViewPartial", entity.Customers.ToList());
        }
        public ActionResult GridViewDeletePartial(int CustomerId)
        {
            if (ModelState.IsValid)
            {
                try
                {
                    entity.Customers.Remove(entity.Customers.Find(CustomerId));
                    // uncomment the next line to enable database updates
                    //entity.SaveChanges();
                }
                catch (Exception e)
                {
                    ViewData["EditError"] = e.Message;
                }
            }
            else
                ViewData["EditError"] = "Please, correct all errors.";
            return PartialView("GridViewPartial", entity.Customers.ToList());
        }
        public ActionResult ComboBoxCountryPartial()
        {
            return GridViewExtension.GetComboBoxCallbackResult(ComboBoxPropertiesProvider.Current.CountryComboBoxProperties);
        }
        public ActionResult ComboBoxCityPartial()
        {
            return GridViewExtension.GetComboBoxCallbackResult(ComboBoxPropertiesProvider.Current.CityComboBoxProperties);
        }
    }

}

Visual Basic
Imports Microsoft.VisualBasic
Imports System.Web.Mvc
Imports E4425.Models
Imports DevExpress.Web.Mvc
Imports System.Linq
Imports System

Namespace E4425.Controllers
    Public Class HomeController
        Inherits Controller
        Private entity As New WorldCitiesEntities()
        Public Function Index() As ActionResult
            Return View(entity.Customers.ToList())
        End Function
        Public Function GridViewPartial() As ActionResult
            Return PartialView(entity.Customers.ToList())
        End Function
        Public Function GridViewEditPartial(ByVal customerInfo As Customer) As ActionResult
            If ModelState.IsValid Then
                Try
                    entity.Customers.Attach(customerInfo)
                    Dim entry = entity.Entry(customerInfo)
                    entry.Property(Function(e) e.CityId).IsModified = True
                    entry.Property(Function(e) e.CountryId).IsModified = True
                    entry.Property(Function(e) e.CustomerName).IsModified = True
                    ' uncomment the next line to enable database updates
                    ' entity.SaveChanges();
                Catch e As Exception
                    ViewData("EditError") = e.Message
                End Try
            Else
                ViewData("EditError") = "Please, correct all errors."
            End If
            Return PartialView("GridViewPartial", entity.Customers.ToList())
        End Function
        Public Function GridViewInsertPartial(ByVal customerInfo As Customer) As ActionResult
            If ModelState.IsValid Then
                Try
                    entity.Customers.Add(customerInfo)
                    ' uncomment the next line to enable database updates
                    ' entity.SaveChanges();
                Catch e As Exception
                    ViewData("EditError") = e.Message
                End Try
            Else
                ViewData("EditError") = "Please, correct all errors."
            End If
            Return PartialView("GridViewPartial", entity.Customers.ToList())
        End Function
        Public Function GridViewDeletePartial(ByVal CustomerId As Integer) As ActionResult
            If ModelState.IsValid Then
                Try
                    entity.Customers.Remove(entity.Customers.Find(CustomerId))
                    'uncomment the next line to enable database updates
                    'entity.SaveChanges();
                Catch e As Exception
                    ViewData("EditError") = e.Message
                End Try
            Else
                ViewData("EditError") = "Please, correct all errors."
            End If
            Return PartialView("GridViewPartial", entity.Customers.ToList())
        End Function
        Public Function ComboBoxCountryPartial() As ActionResult
            Return GridViewExtension.GetComboBoxCallbackResult(ComboBoxPropertiesProvider.Current.CountryComboBoxProperties)
        End Function
        Public Function ComboBoxCityPartial() As ActionResult
            Return GridViewExtension.GetComboBoxCallbackResult(ComboBoxPropertiesProvider.Current.CityComboBoxProperties)
        End Function
    End Class
End Namespace

Global.asax

Code
<%@ Application Codebehind="Global.asax.cs" Inherits="E4425.MvcApplication" Language="C#" %>

Global.asax.cs(vb)

C#
VB.NET

C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;

namespace E4425
{
    // Note: For instructions on enabling IIS6 or IIS7 classic mode, 
    // visit http://go.microsoft.com/?LinkId=9394801

    public class MvcApplication : System.Web.HttpApplication
    {
        public static void RegisterGlobalFilters(GlobalFilterCollection filters)
        {
            filters.Add(new HandleErrorAttribute());
        }

        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
            routes.IgnoreRoute("{resource}.ashx/{*pathInfo}");

            routes.MapRoute(
                "Default", // Route name
                "{controller}/{action}/{id}", // URL with parameters
                new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
            );

        }

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            RegisterGlobalFilters(GlobalFilters.Filters);
            RegisterRoutes(RouteTable.Routes);
            
            ModelBinders.Binders.DefaultBinder = new DevExpress.Web.Mvc.DevExpressEditorsBinder();
        }
    }
}

Visual Basic
Imports Microsoft.VisualBasic
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Web
Imports System.Web.Mvc
Imports System.Web.Routing

Namespace E4425
    ' Note: For instructions on enabling IIS6 or IIS7 classic mode, 
    ' visit http://go.microsoft.com/?LinkId=9394801

    Public Class MvcApplication
        Inherits System.Web.HttpApplication
        Public Shared Sub RegisterGlobalFilters(ByVal filters As GlobalFilterCollection)
            filters.Add(New HandleErrorAttribute())
        End Sub

        Public Shared Sub RegisterRoutes(ByVal routes As RouteCollection)
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}")
            routes.IgnoreRoute("{resource}.ashx/{*pathInfo}")

            routes.MapRoute("Default", "{controller}/{action}/{id}", New With {Key .controller = "Home", Key .action = "Index", Key .id = UrlParameter.Optional})

        End Sub

        Protected Sub Application_Start()
            AreaRegistration.RegisterAllAreas()

            RegisterGlobalFilters(GlobalFilters.Filters)
            RegisterRoutes(RouteTable.Routes)

            ModelBinders.Binders.DefaultBinder = New DevExpress.Web.Mvc.DevExpressEditorsBinder()
        End Sub
    End Class
End Namespace

Models/City.cs(vb)

C#
VB.NET

C#
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace E4425.Models
{
    using System;
    using System.Collections.Generic;
    
    public partial class City
    {
        public City()
        {
            this.Countries = new HashSet<Country>();
            this.Customers = new HashSet<Customer>();
        }
    
        public int CityId { get; set; }
        public string CityName { get; set; }
        public Nullable<int> CountryId { get; set; }
    
        public virtual Country Country { get; set; }
        public virtual ICollection<Country> Countries { get; set; }
        public virtual ICollection<Customer> Customers { get; set; }
    }
}

Visual Basic
'------------------------------------------------------------------------------
' <auto-generated>
'    This code was generated from a template.
'
'    Manual changes to this file may cause unexpected behavior in your application.
'    Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------


Imports Microsoft.VisualBasic
    Imports System
    Imports System.Collections.Generic
Namespace E4425.Models

    Partial Public Class City
        Public Sub New()
            Me.Countries = New HashSet(Of Country)()
            Me.Customers = New HashSet(Of Customer)()
        End Sub

        Private privateCityId As Integer
        Public Property CityId() As Integer
            Get
                Return privateCityId
            End Get
            Set(ByVal value As Integer)
                privateCityId = value
            End Set
        End Property
        Private privateCityName As String
        Public Property CityName() As String
            Get
                Return privateCityName
            End Get
            Set(ByVal value As String)
                privateCityName = value
            End Set
        End Property
        Private privateCountryId? As Integer
        Public Property CountryId() As Integer?
            Get
                Return privateCountryId
            End Get
            Set(ByVal value? As Integer)
                privateCountryId = value
            End Set
        End Property

        Private privateCountry As Country
        Public Overridable Property Country() As Country
            Get
                Return privateCountry
            End Get
            Set(ByVal value As Country)
                privateCountry = value
            End Set
        End Property
        Private privateCountries As ICollection(Of Country)
        Public Overridable Property Countries() As ICollection(Of Country)
            Get
                Return privateCountries
            End Get
            Set(ByVal value As ICollection(Of Country))
                privateCountries = value
            End Set
        End Property
        Private privateCustomers As ICollection(Of Customer)
        Public Overridable Property Customers() As ICollection(Of Customer)
            Get
                Return privateCustomers
            End Get
            Set(ByVal value As ICollection(Of Customer))
                privateCustomers = value
            End Set
        End Property
    End Class
End Namespace

Models/ComboBoxPropertiesProvider.cs(vb)

C#
VB.NET

C#
using DevExpress.Web;
using DevExpress.Web.Mvc;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI.WebControls;

namespace E4425.Models
{
    public class ComboBoxPropertiesProvider : IDisposable
    {

        static ComboBoxPropertiesProvider current;
        public static ComboBoxPropertiesProvider Current
        {
            get
            {
                if (current == null)
                    current = new ComboBoxPropertiesProvider();
                return current;
            }
        }

        public int EditableCountryID
        {
            get
            {
                string rawCountryId = HttpContext.Current.Request["CountryId"];
                return string.IsNullOrEmpty(rawCountryId) ? -1 : int.Parse(rawCountryId);
            }
        }
        MVCxColumnComboBoxProperties cityComboBoxProperties;
        public MVCxColumnComboBoxProperties CityComboBoxProperties
        {
            get
            {
                if (cityComboBoxProperties == null)
                    cityComboBoxProperties = CreateCityComboBox();
                return cityComboBoxProperties;
            }
        }

        MVCxColumnComboBoxProperties countryComboBoxProperties;
        public MVCxColumnComboBoxProperties CountryComboBoxProperties
        {
            get
            {
                if (countryComboBoxProperties == null)
                    countryComboBoxProperties = CreateCountryComboBox();
                return countryComboBoxProperties;
            }
        }

        WorldCitiesEntities worldCities;
        protected WorldCitiesEntities WorldCities
        {
            get
            {
                if (worldCities == null)
                    worldCities = new WorldCitiesEntities();
                return worldCities;
            }
        }

        protected MVCxColumnComboBoxProperties CreateCountryComboBox()
        {
            MVCxColumnComboBoxProperties cs = new MVCxColumnComboBoxProperties();
            cs.CallbackRouteValues = new { Controller = "Home", Action = "ComboBoxCountryPartial" };
            cs.Width = Unit.Percentage(100);
            cs.TextField = "CountryName";
            cs.ValueField = "CountryId";
            cs.ValueType = typeof(int);
            cs.IncrementalFilteringDelay = 1000;
            cs.IncrementalFilteringMode = IncrementalFilteringMode.Contains;
            cs.FilterMinLength = 2;
            cs.CallbackPageSize = 20;
            cs.ClientSideEvents.SelectedIndexChanged = "CountriesCombo_SelectedIndexChanged";
            cs.BindList(WorldCities.Countries.ToList());
            return cs;
        }
        protected MVCxColumnComboBoxProperties CreateCityComboBox()
        {
            MVCxColumnComboBoxProperties cs = new MVCxColumnComboBoxProperties();
            cs.CallbackRouteValues = new { Controller = "Home", Action = "ComboBoxCityPartial" };
            cs.Width = Unit.Percentage(100);
            cs.CallbackPageSize = 20;
            cs.TextField = "CityName";
            cs.ValueField = "CityId";
            cs.ValueType = typeof(int);
            cs.IncrementalFilteringDelay = 1000;
            cs.IncrementalFilteringMode = IncrementalFilteringMode.Contains;
            cs.FilterMinLength = 2;
            cs.BindList(OnItemsRequestedByFilterCondition, OnItemRequestedByValue);
            cs.ClientSideEvents.BeginCallback = "CitiesCombo_BeginCallback";
            cs.ClientSideEvents.EndCallback = "CitiesCombo_EndCallback";
            return cs;
        }

        protected object OnItemRequestedByValue(ListEditItemRequestedByValueEventArgs e)
        {
            int id;
            if (e.Value == null || !int.TryParse(e.Value.ToString(), out id))
                return null;
            var query = WorldCities.Cities.Where(city => city.CityId == id);
            return query.ToList();

        }
        protected object OnItemsRequestedByFilterCondition(ListEditItemsRequestedByFilterConditionEventArgs e)
        {
            IQueryable<City> query;
            var skip = e.BeginIndex;
            var take = e.EndIndex - e.BeginIndex + 1;
            if (EditableCountryID > -1)
                query = WorldCities.Cities.Where(city => city.CityName.Contains(e.Filter) && city.Country.CountryId == EditableCountryID).OrderBy(city => city.CityId);
            else
                query = WorldCities.Cities.Where(city => city.CityName.Contains(e.Filter)).OrderBy(city => city.CityId);
            query = query.Skip(skip).Take(take);
            return query.ToList();
        }

        #region IDisposable Members
        public void Dispose()
        {
            if (this.worldCities != null)
                worldCities.Dispose();
        }
        #endregion
    }
}

Visual Basic
Imports Microsoft.VisualBasic
Imports DevExpress.Web
Imports DevExpress.Web.Mvc
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Web
Imports System.Web.UI.WebControls

Namespace E4425.Models
    Public Class ComboBoxPropertiesProvider
        Implements IDisposable

        Private Shared _current As ComboBoxPropertiesProvider
        Public Shared ReadOnly Property Current() As ComboBoxPropertiesProvider
            Get
                If _current Is Nothing Then
                    _current = New ComboBoxPropertiesProvider()
                End If
                Return _current
            End Get
        End Property

        Public ReadOnly Property EditableCountryID() As Integer
            Get
                Dim rawCountryId As String = HttpContext.Current.Request("CountryId")
                Return If(String.IsNullOrEmpty(rawCountryId), -1, Integer.Parse(rawCountryId))
            End Get
        End Property
        Private _cityComboBoxProperties As MVCxColumnComboBoxProperties
        Public ReadOnly Property CityComboBoxProperties() As MVCxColumnComboBoxProperties
            Get
                If _cityComboBoxProperties Is Nothing Then
                    _cityComboBoxProperties = CreateCityComboBoxProperties()
                End If
                Return _cityComboBoxProperties
            End Get
        End Property

        Private _countryComboBoxProperties As MVCxColumnComboBoxProperties
        Public ReadOnly Property CountryComboBoxProperties() As MVCxColumnComboBoxProperties
            Get
                If _countryComboBoxProperties Is Nothing Then
                    _countryComboBoxProperties = CreateCountryComboBox()
                End If
                Return _countryComboBoxProperties
            End Get
        End Property

        Private worldCities_Renamed As WorldCitiesEntities
        Protected ReadOnly Property WorldCities() As WorldCitiesEntities
            Get
                If worldCities_Renamed Is Nothing Then
                    worldCities_Renamed = New WorldCitiesEntities()
                End If
                Return worldCities_Renamed
            End Get
        End Property

        Protected Function CreateCountryComboBox() As MVCxColumnComboBoxProperties
            Dim cs As New MVCxColumnComboBoxProperties()
            cs.CallbackRouteValues = New With {Key .Controller = "Home", Key .Action = "ComboBoxCountryPartial"}
            cs.Width = Unit.Percentage(100)
            cs.TextField = "CountryName"
            cs.ValueField = "CountryId"
            cs.ValueType = GetType(Integer)
            cs.IncrementalFilteringDelay = 1000
            cs.IncrementalFilteringMode = IncrementalFilteringMode.Contains
            cs.FilterMinLength = 2
            cs.CallbackPageSize = 20
            cs.ClientSideEvents.SelectedIndexChanged = "CountriesCombo_SelectedIndexChanged"
            cs.BindList(WorldCities.Countries.ToList())
            Return cs
        End Function
        Protected Function CreateCityComboBoxProperties() As MVCxColumnComboBoxProperties
            Dim cs As New MVCxColumnComboBoxProperties()
            cs.CallbackRouteValues = New With {Key .Controller = "Home", Key .Action = "ComboBoxCityPartial"}
            cs.Width = Unit.Percentage(100)
            cs.CallbackPageSize = 20
            cs.TextField = "CityName"
            cs.ValueField = "CityId"
            cs.ValueType = GetType(Integer)
            cs.IncrementalFilteringDelay = 1000
            cs.IncrementalFilteringMode = IncrementalFilteringMode.Contains
            cs.FilterMinLength = 2
            cs.BindList(AddressOf OnItemsRequestedByFilterCondition, AddressOf OnItemRequestedByValue)
            cs.ClientSideEvents.BeginCallback = "CitiesCombo_BeginCallback"
            cs.ClientSideEvents.EndCallback = "CitiesCombo_EndCallback"
            Return cs
        End Function

        Protected Function OnItemRequestedByValue(ByVal e As ListEditItemRequestedByValueEventArgs) As Object
            Dim id As Integer
            If e.Value Is Nothing OrElse (Not Integer.TryParse(e.Value.ToString(), id)) Then
                Return Nothing
            End If
            Dim query = WorldCities.Cities.Where(Function(city) city.CityId = id)
            Return query.ToList()

        End Function
        Protected Function OnItemsRequestedByFilterCondition(ByVal e As ListEditItemsRequestedByFilterConditionEventArgs) As Object
            Dim query As IQueryable(Of City)
            Dim skip = e.BeginIndex
            Dim take = e.EndIndex - e.BeginIndex + 1
            If EditableCountryID > -1 Then
                query = WorldCities.Cities.Where(Function(city) city.CityName.Contains(e.Filter) AndAlso city.Country.CountryId = EditableCountryID).OrderBy(Function(city) city.CityId)
            Else
                query = WorldCities.Cities.Where(Function(city) city.CityName.Contains(e.Filter)).OrderBy(Function(city) city.CityId)
            End If
            query = query.Skip(skip).Take(take)
            Return query.ToList()
        End Function

        #Region "IDisposable Members"
        Public Sub Dispose() Implements IDisposable.Dispose
            If Me.worldCities_Renamed IsNot Nothing Then
                worldCities_Renamed.Dispose()
            End If
        End Sub
        #End Region
    End Class
End Namespace

Models/Country.cs(vb)

C#
VB.NET

C#
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace E4425.Models
{
    using System;
    using System.Collections.Generic;
    
    public partial class Country
    {
        public Country()
        {
            this.Cities = new HashSet<City>();
            this.Customers = new HashSet<Customer>();
        }
    
        public int CountryId { get; set; }
        public string CountryName { get; set; }
        public Nullable<int> CapitalId { get; set; }
    
        public virtual ICollection<City> Cities { get; set; }
        public virtual City City { get; set; }
        public virtual ICollection<Customer> Customers { get; set; }
    }
}

Visual Basic
'------------------------------------------------------------------------------
' <auto-generated>
'    This code was generated from a template.
'
'    Manual changes to this file may cause unexpected behavior in your application.
'    Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------


Imports Microsoft.VisualBasic
    Imports System
    Imports System.Collections.Generic
Namespace E4425.Models

    Partial Public Class Country
        Public Sub New()
            Me.Cities = New HashSet(Of City)()
            Me.Customers = New HashSet(Of Customer)()
        End Sub

        Private privateCountryId As Integer
        Public Property CountryId() As Integer
            Get
                Return privateCountryId
            End Get
            Set(ByVal value As Integer)
                privateCountryId = value
            End Set
        End Property
        Private privateCountryName As String
        Public Property CountryName() As String
            Get
                Return privateCountryName
            End Get
            Set(ByVal value As String)
                privateCountryName = value
            End Set
        End Property
        Private privateCapitalId? As Integer
        Public Property CapitalId() As Integer?
            Get
                Return privateCapitalId
            End Get
            Set(ByVal value? As Integer)
                privateCapitalId = value
            End Set
        End Property

        Private privateCities As ICollection(Of City)
        Public Overridable Property Cities() As ICollection(Of City)
            Get
                Return privateCities
            End Get
            Set(ByVal value As ICollection(Of City))
                privateCities = value
            End Set
        End Property
        Private privateCity As City
        Public Overridable Property City() As City
            Get
                Return privateCity
            End Get
            Set(ByVal value As City)
                privateCity = value
            End Set
        End Property
        Private privateCustomers As ICollection(Of Customer)
        Public Overridable Property Customers() As ICollection(Of Customer)
            Get
                Return privateCustomers
            End Get
            Set(ByVal value As ICollection(Of Customer))
                privateCustomers = value
            End Set
        End Property
    End Class
End Namespace

Models/Customer.cs(vb)

C#
VB.NET

C#
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace E4425.Models
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel.DataAnnotations;

    public partial class Customer
    {
        public int CustomerId { get; set; }
        [Required(ErrorMessage = "Customer cannot be empty")]
        public string CustomerName { get; set; }
        [Required(ErrorMessage = "Country should be chosen")]
        public Nullable<int> CountryId { get; set; }
        [Required(ErrorMessage = "City should be chosen")]
        public Nullable<int> CityId { get; set; }

        public virtual City City { get; set; }
        public virtual Country Country { get; set; }
    }
}

Visual Basic
'------------------------------------------------------------------------------
' <auto-generated>
'    This code was generated from a template.
'
'    Manual changes to this file may cause unexpected behavior in your application.
'    Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------


Imports Microsoft.VisualBasic
Imports System
Imports System.Collections.Generic
Imports System.ComponentModel.DataAnnotations

Namespace E4425.Models

    Partial Public Class Customer
        Private privateCustomerId As Integer
        Public Property CustomerId() As Integer
            Get
                Return privateCustomerId
            End Get
            Set(ByVal value As Integer)
                privateCustomerId = value
            End Set
        End Property
        Private privateCustomerName As String
        <Required(ErrorMessage:="Customer cannot be empty")> _
        Public Property CustomerName() As String
            Get
                Return privateCustomerName
            End Get
            Set(ByVal value As String)
                privateCustomerName = value
            End Set
        End Property
        Private privateCountryId? As Integer
        <Required(ErrorMessage:="Country should be chosen")>
        Public Property CountryId() As Integer?
            Get
                Return privateCountryId
            End Get
            Set(ByVal value As Integer?)
                privateCountryId = value
            End Set
        End Property
        Private privateCityId? As Integer
        <Required(ErrorMessage:="City should be chosen")>
        Public Property CityId() As Integer?
            Get
                Return privateCityId
            End Get
            Set(ByVal value As Integer?)
                privateCityId = value
            End Set
        End Property

        Private privateCity As City
        Public Overridable Property City() As City
            Get
                Return privateCity
            End Get
            Set(ByVal value As City)
                privateCity = value
            End Set
        End Property
        Private privateCountry As Country
        Public Overridable Property Country() As Country
            Get
                Return privateCountry
            End Get
            Set(ByVal value As Country)
                privateCountry = value
            End Set
        End Property
    End Class
End Namespace

Models/WoldCitiesModel.Context.cs(vb)

C#
VB.NET

C#
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace E4425.Models
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Infrastructure;
    
    public partial class WorldCitiesEntities : DbContext
    {
        public WorldCitiesEntities()
            : base("name=WorldCitiesEntities")
        {
        }
    
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            throw new UnintentionalCodeFirstException();
        }
    
        public DbSet<City> Cities { get; set; }
        public DbSet<Country> Countries { get; set; }
        public DbSet<Customer> Customers { get; set; }
    }
}

Visual Basic
'------------------------------------------------------------------------------
' <auto-generated>
'    This code was generated from a template.
'
'    Manual changes to this file may cause unexpected behavior in your application.
'    Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------


Imports Microsoft.VisualBasic
    Imports System
    Imports System.Data.Entity
    Imports System.Data.Entity.Infrastructure
Namespace E4425.Models

    Partial Public Class WorldCitiesEntities
        Inherits DbContext
        Public Sub New()
            MyBase.New("name=WorldCitiesEntities")
        End Sub

        Protected Overrides Sub OnModelCreating(ByVal modelBuilder As DbModelBuilder)
            Throw New UnintentionalCodeFirstException()
        End Sub

        Private privateCities As DbSet(Of City)
        Public Property Cities() As DbSet(Of City)
            Get
                Return privateCities
            End Get
            Set(ByVal value As DbSet(Of City))
                privateCities = value
            End Set
        End Property
        Private privateCountries As DbSet(Of Country)
        Public Property Countries() As DbSet(Of Country)
            Get
                Return privateCountries
            End Get
            Set(ByVal value As DbSet(Of Country))
                privateCountries = value
            End Set
        End Property
        Private privateCustomers As DbSet(Of Customer)
        Public Property Customers() As DbSet(Of Customer)
            Get
                Return privateCustomers
            End Get
            Set(ByVal value As DbSet(Of Customer))
                privateCustomers = value
            End Set
        End Property
    End Class
End Namespace

Models/WoldCitiesModel.cs(vb)

C#
VB.NET

C#
//------------------------------------------------------------------------------
// <auto-generated>
//    This code was generated from a template.
//
//    Manual changes to this file may cause unexpected behavior in your application.
//    Manual changes to this file will be overwritten if the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

Visual Basic
'
Imports Microsoft.VisualBasic
Imports System
'------------------------------------------------------------------------------
' <auto-generated>
'    This code was generated from a template.
'
'    Manual changes to this file may cause unexpected behavior in your application.
'    Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

Views/Home/GridViewPartial.cshtml

Razor
@using E4425.Models;

@(Html.DevExpress().GridView<Customer>(settings =>
{
    settings.Name = "grid";
    settings.KeyFields(c => c.CustomerId);
    settings.Width = System.Web.UI.WebControls.Unit.Pixel(500);
    settings.CallbackRouteValues = new { Controller = "Home", Action = "GridViewPartial" };

    settings.SettingsEditing.Mode = GridViewEditingMode.EditForm;
    settings.SettingsEditing.UpdateRowRouteValues = new { Controller = "Home", Action = "GridViewEditPartial" };
    settings.SettingsEditing.AddNewRowRouteValues = new { Controller = "Home", Action = "GridViewInsertPartial" };
    settings.SettingsEditing.DeleteRowRouteValues = new { Controller = "Home", Action = "GridViewDeletePartial" };

    settings.CommandColumn.Visible = true;
    settings.CommandColumn.ShowNewButtonInHeader = true;
    settings.CommandColumn.ShowDeleteButton = true;
    settings.CommandColumn.ShowEditButton = true;

    settings.Columns.Add(c => c.CustomerId).Visible = false;
    settings.Columns.Add(c => c.CustomerName);
    settings.SettingsEditing.ShowModelErrorsForEditors = true;
    settings.Columns.Add(c => c.CountryId, country =>
    {
        country.Caption = "Country";
        country.EditorProperties().ComboBox(cs => cs.Assign(ComboBoxPropertiesProvider.Current.CountryComboBoxProperties));
    });
    settings.Columns.Add(c => c.CityId, city =>
    {
        city.Caption = "City";
        city.EditorProperties().ComboBox(cs => cs.Assign(ComboBoxPropertiesProvider.Current.CityComboBoxProperties));
    });
    settings.CellEditorInitialize = (s, e) =>
    {
        ASPxEdit editor = (ASPxEdit)e.Editor;
        editor.ValidationSettings.Display = Display.Dynamic;
    };

    settings.ClientSideEvents.BeginCallback = "onBeginCallback";
    settings.ClientSideEvents.EndCallback = "onEndCallback";
}).SetEditErrorText(ViewData["EditError"] as string).Bind(Model).GetHtml())

Views/Home/Index.cshtml

Razor
@{
    ViewBag.Title = "GridView - How to implement cascading comboboxes in the EditForm";  
}
<script type="text/javascript">
    var customCallback = false;
    var editingStart = false;
    var previousValue = null;
    function onBeginCallback(s, e) {
        if (e.command = "STARTEDIT")
            editingStart = true;
    }
    function onEndCallback(s, e) {
        if (editingStart) {
            customCallback = true;
            var editor = grid.GetEditor('CityId');
            if (editor) {
                previousValue = editor.GetValue();
                editor.PerformCallback();
            }
        }
    }
    function CountriesCombo_SelectedIndexChanged(s, e) {
        customCallback = true;
        grid.GetEditor('CityId').PerformCallback();
    }
    function CitiesCombo_BeginCallback(s, e) {
        e.customArgs['CountryId'] = grid.GetEditor('CountryId').GetValue();
    }
    function CitiesCombo_EndCallback(s, e) {
        var editor = MVCxClientComboBox.Cast(s);
        if (customCallback) {
            customCallback = false;
            if (previousValue) {
                editor.SetValue(previousValue);
                previousValue = null;
            } else {
                editor.SetSelectedIndex(0);
            }
        }
    }
</script>
@using (Html.BeginForm())
{
    @Html.Partial("GridViewPartial")
}

Mike (DevExpress)

last modified 2 years ago

Modified: April 27, 2023 7:41 AM

Platform: ASP.NET MVC

Product: MVC GridView

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