c# - Select multiple items from a DataGrid in an MVVM WPF project -

how can select multiple items datagrid in mvvm wpf project?

you can add custom dependency property this:

public class customdatagrid : datagrid {     public customdatagrid ()     {         this.selectionchanged += customdatagrid_selectionchanged;     }      void customdatagrid_selectionchanged (object sender, selectionchangedeventargs e)     {         this.selecteditemslist = this.selecteditems;     }     #region selecteditemslist      public ilist selecteditemslist     {         { return (ilist)getvalue (selecteditemslistproperty); }         set { setvalue (selecteditemslistproperty, value); }     }      public static readonly dependencyproperty selecteditemslistproperty =             dependencyproperty.register ("selecteditemslist", typeof (ilist), typeof (customdatagrid), new propertymetadata (null));      #endregion } 

now can use datagrid in xaml:

<window x:class="datagridtesting.mainwindow"     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"     xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"     xmlns:local="clr-namespace:datagridtesting.customdatagrid"     title="mainwindow"     height="350"     width="525">   <dockpanel>     <local:customdatagrid itemssource="{binding model}"         selectionmode="extended"         alternatingrowbackground="aquamarine"         selectionunit="fullrow"         isreadonly="true"         snapstodevicepixels="true"         selecteditemslist="{binding testselected, mode=twoway, updatesourcetrigger=propertychanged}"/>   </dockpanel> </window> 

my viewmodel:

public class myviewmodel : inotifypropertychanged {     private static object _lock = new object ();     private list<mymodel> _mymodel;      public ienumerable<mymodel> model { { return _mymodel; } }      private ilist _selectedmodels = new arraylist ();      public ilist testselected     {         { return _selectedmodels; }         set         {             _selectedmodels = value;             raisepropertychanged ("testselected");         }     }      public myviewmodel ()     {         _mymodel = new list<mymodel> ();         bindingoperations.enablecollectionsynchronization (_mymodel, _lock);          (int = 0; < 10; i++)         {             _mymodel.add (new mymodel             {                 name = "test " + i,                 age = * 22             });         }         raisepropertychanged ("model");     }      public event propertychangedeventhandler propertychanged;      public void raisepropertychanged (string propertyname)     {         var pc = propertychanged;         if (pc != null)             pc (this, new propertychangedeventargs (propertyname));     } } 

my model:

public class mymodel {     public string name { get; set; }     public int age { get; set; } } 

and finally, here code behind of mainwindow:

public partial class mainwindow : window {     public mainwindow ()     {         initializecomponent ();         this.datacontext = new myviewmodel ();     } } 

i hope clean mvvm design helps.