How add items Text Value to ComboBox read them in SelectedIndexChanged SelectedValue null

Question

I want to add some items to a combobox like this       public class ComboboxItem       public string Text   get  set        public object Value   get  set         public override string ToString                 return Text           ComboboxItem item   new ComboboxItem    item Text    choose a server      item Value    -1   ComboBox Servers Items Add item            and read those texts and values in SelectedIndexChanged like this       private void ComboBox Servers SelectedIndexChanged object sender  EventArgs e        MessageBox Show ComboBox Servers SelectedValue ToString         But SelectedValue is always null  what is the problem and how can I fix it

User · Answer

try this   ComboBox cbx   new ComboBox    cbx DisplayMember    Text   cbx ValueMember    Value     EDIT  a little explanation  sory  I also didn t notice your combobox wasn t bound  I blame the lack of caffeine    The difference between SelectedValue and SelectedItem are explained pretty well here  ComboBox SelectedItem vs SelectedValue  So  if your combobox is not bound to datasource  DisplayMember and ValueMember doesn t do anything  and SelectedValue will always be null  SelectedValueChanged won t be called  So either bind your combobox               comboBox1 DisplayMember    Text               comboBox1 ValueMember    Value                List lt ComboboxItem gt  list   new List lt ComboboxItem gt                  ComboboxItem item   new ComboboxItem                item Text    choose a server                  item Value    -1               list Add item                item   new ComboboxItem                item Text    S1               item Value    1               list Add item                item   new ComboboxItem                item Text    S2               item Value    2               list Add item                cbx DataSource   list     bind combobox to a datasource   or use SelectedItem property   if  cbx SelectedItem    null               Console WriteLine  ITEM    comboBox1 SelectedItem ToString

User · Answer

This is similar to some of the other answers  but is compact and avoids the conversion to dictionary if you already have a list   Given a ComboBox  combobox  on a windows form and a class SomeClass with the string type property Name   List lt SomeClass gt  list   new List lt SomeClass gt      combobox DisplayMember    Name   combobox DataSource   list    Which means that combobox SelectedItem is a SomeClass object from list  and each item in combobox will be displayed using its property Name   You can read the selected item using  SomeClass someClass    SomeClass combobox SelectedItem

User · Answer

Dictionary lt int string gt  comboSource   new Dictionary lt int string gt     comboSource Add 1   Sunday    comboSource Add 2   Monday      Aftr adding values to Dictionary  use this as combobox datasource   comboBox1 DataSource   new BindingSource comboSource  null   comboBox1 DisplayMember    Value   comboBox1 ValueMember    Key

User · Answer

combo1 DisplayMember    Text           combo1 ValueMember    Value              combo1 Items Add new   Text    someText    Value    someValue               dynamic item   combo1 Items combo1 SelectedIndex           var itemValue   item Value          var itemText   item Text    Unfortunatly  combo1 SelectedValue  does not work  i did not want to bind my combobox with any source  so i came up with this solution  Maybe it will help someone

User · Answer

You can take the SelectedItem and cast it back to your class and access its properties    MessageBox Show   ComboboxItem ComboBox Countries In Silvers SelectedItem  Value     Edit You can try using DataTextField and DataValueField  I used it with DataSource    ComboBox Servers DataTextField    Text   ComboBox Servers DataValueField    Value

[c#] How add items(Text & Value) to ComboBox & read them in SelectedIndexChanged (SelectedValue = null)

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