vb.net - I want to know how to add items to an arraylist -

here code:-

   if firstnametext.text = ""         messagebox.show("please enter first name please")     end if     if surnametext.text = ""         messagebox.show("please enter surname please")     end if     if (not rb_male.checked) andalso (not rb_female.checked)         messagebox.show("please select gender")     end if     if combobox1.selectedvalue = false         messagebox.show("please select year group")     end if     if textstudentid.text = ""         messagebox.show("please select generate button give unique student id")     end if      "in section want add submitted items arraylist user's name pops in list box"     try      catch ex exception      end try 

that's bit of code have written , have looked everywhere answer submit items arraylist. " " area i'm planning submit items arraylist. or link guide do.

first, make class student information

class student     public firstname string     public surname string     public gender string     public yeargroup string     public studentid string end class 

second, use list not arraylist, , make sure @ class level can used throughout code

private studentlist new list(of student) 

third, after validate data controls on form, instantiate student object , add studentlist. once you're done adding new student data, can access studentlist in other methods whatever want

' validate fields have data new student if string.isnullorempty(firstnametext.text)     messagebox.show("please enter first name please")     firstnametext.focus()     return elseif string.isnullorempty(surnametext.text)     messagebox.show("please enter surname please")     surnametext.focus()     return elseif not rb_male.checked andalso not rb_female.checked     messagebox.show("please select gender")     return elseif combobox1.selectedindex = -1     messagebox.show("please select year group")     return elseif string.isnullorempty(textstudentid.text)     messagebox.show("please select generate button give unique student id")     generatebutton.focus()     return end if  ' create new student object dim newstudent new student() newstudent.firstname = firstnametext.text newstudent.surname = surnametext.text if rb_male.checked     newstudent.gender = "m" else     newstudent.gender = "f" end if newstudent.yeargroup = combobox1.selecteditem newstudent.studentid = textstudentid.text  ' add new student object list studentlist.add(newstudent)