foreach - C# mutilple forms open instead of one -

what did was, created number of instances of different people , added each person list called listofpeople , have each person's named in listbox. created new form print out details of person select listbox, when select 1 person, of details open in multiple forms. example if have bill & jill in listofpeople , view details bill, 2 forms open up, 1 showing details bill , other jill.

how can fix 1 form opens?

//this create instance open details form person private void detailsbutton_click(object sender, eventargs e) {        if (peoplelistbox.selecteditem == null)         {             messagebox.show("no person selected!");         }         else          {                             foreach (person person in listofpeople)             {                 persondetails persondetails = new persondetails(person);                 persondetails.show();             }          }  }      public partial class persondetails : form   {     //this constructor takes in parameter , prints data     public persondetails(person person)     {         initializecomponent();         displaynamelabel.text = person.printdata().tostring();     }   } 

assuming items in listbox persons, need use selecteditem create single person. in code above, foreach loop explicitly creates , shows form each person in list. i'm not quite sure why confused behavior.

private void detailsbutton_click(object sender, eventargs e) {     if (peoplelistbox.selecteditem == null)     {         messagebox.show("no person selected!");     }     else     {         persondetails persondetails =                          new persondetails(peoplelistbox.selecteditem);         persondetails.show();     } } 

if selecteditem isn't person, need way map selecteditem particular item in listofpeople. instance, if selecteditem string representation of name, , listofpeople dictionary<string, person>, persondetails persondetails = listofpeople[peoplelistbox.selecteditem];.