c# - WPF Datagrid single click row to open new Page -

my first post here! , new coding!...

i have wpf datagrid in frame on page. click (preferably single click) on row , use id value stored in 1 of columns navigate (open) new page.

using mousedoubleclick can double click row open page. throwing: "an unhandled exception of type 'system.nullreferenceexception' occurred in program.exe additional information: object reference not set instance of object."

on line (see code behind below complete method):

string id = ((datarowview)persondatagrid.selecteditem).row["personid"].tostring(); 

xaml:

<datagrid x:name="persondatagrid" autogeneratecolumns="false"       selectionmode="single" selectionunit ="fullrow"            mousedoubleclick="persondatagrid_cellclicked"  >   <datagrid.columns>       <datagridtextcolumn binding="{binding path=personid}"            clipboardcontentbinding="{x:null}" header="id"  />   </datagrid.columns>   <datagrid.cellstyle>       <style targettype="datagridcell" basedon="{staticresource mydatagridcellstyle}">            <eventsetter event="datagridcell.mouseleftbuttondown" handler="persondatagrid_cellclicked"/>       </style>    </datagrid.cellstyle> </datagrid> 

code behind:

private void persondatagrid_cellclicked(object sender, mousebuttoneventargs e)      {         string id = ((datarowview)persondatagrid.selecteditem).row["personid"].tostring();          selectedpersonid = int32.parse(id);          this.navigationservice.navigate(new personprofile());     } 

is there better way open personprofile page? there easy way open page using single click on row?

thanks.

a better way it, define collection of person define datagrid itemsource , property of type person contains selected item in datagrid:

 <datagrid x:name="persondatagrid" autogeneratecolumns="false"              selectionmode="single" selectionunit ="fullrow"                    mouserightbuttonup="persondatagrid_cellclicked"                itemssource="{binding persons}"                selecteditem="{binding selectedperson}">         <datagrid.columns>             <datagridtextcolumn binding="{binding path=personid}" header="id"  />             <datagridtextcolumn binding="{binding path=personname}" header="name"  />         </datagrid.columns>     </datagrid> 

and selectedperson , persons defined in code behind of page :

 public partial class page1 : page,inotifypropertychanged {     private observablecollection<person> _persons ;     public observablecollection<person> persons     {                 {             return _persons;         }          set         {             if (_persons == value)             {                 return;             }              _persons = value;              onpropertychanged();         }     }      private person _selectedperson ;     public person selectedperson     {                 {             return _selectedperson;         }          set         {             if (_selectedperson == value)             {                 return;             }              _selectedperson = value;             onpropertychanged();         }     }     public page1()     {         initializecomponent();     }      public event propertychangedeventhandler propertychanged;     [notifypropertychangedinvocator]     protected virtual void onpropertychanged([callermembername] string propertyname = null)     {         propertychangedeventhandler handler = propertychanged;         if (handler != null) handler(this, new propertychangedeventargs(propertyname));     } } public class person {    public int personid { get; set; }    public string personname { get; set; } } 

the inotifypropertychanged used notify ui of changes in properties. use selectedperson property or pass new page, when receive mouserightbuttonup event example in datagrid:

    private void persondatagrid_cellclicked(object sender, mousebuttoneventargs e)     {         if (selectedperson == null)             return;         this.navigationservice.navigate(new personprofile(selectedperson));     } 

and change personprofile page receive person in constructor.