c# - Hitting Enter in Combobox clears text -

i have combo box list of items. when user starts typing drop down should open. hitting key should check text of combo box.

to accomplish set droppeddown = true inside keydown event. however, after did hitting key causes text of combo box empty.

private void cmbitems_keydown(object sender, keyeventargs e) {     if (!e.keycode.equals(keys.enter)) {         if (!cmbitems.droppeddown) {             cmbitems.droppeddown = true;         }     }     else {         //check text     } } 

why combo box text cleared , there way around it?

my users prefer not use autocompletemode.suggestappend instead, if have to.

full sample code:

public class demo : form {     private system.componentmodel.icontainer components = null;      protected override void dispose(bool disposing)     {         if (disposing && (components != null)) {             components.dispose();         }         base.dispose(disposing);     }      private void initializecomponent()     {         this.lbltext = new system.windows.forms.label();         this.cmbitems = new system.windows.forms.combobox();         this.suspendlayout();         //          // lbltext         //          this.lbltext.autosize = true;         this.lbltext.location = new system.drawing.point(152, 47);         this.lbltext.name = "lbltext";         this.lbltext.size = new system.drawing.size(155, 13);         this.lbltext.tabindex = 17;         this.lbltext.text = "text";         //          // cmbitems         //          this.cmbitems.autocompletemode = system.windows.forms.autocompletemode.append;         this.cmbitems.autocompletesource = system.windows.forms.autocompletesource.listitems;         this.cmbitems.location = new system.drawing.point(12, 44);         this.cmbitems.name = "cmbitems";         this.cmbitems.size = new system.drawing.size(121, 21);         this.cmbitems.tabindex = 0;         this.cmbitems.keydown += new system.windows.forms.keyeventhandler(this.cmbitems_keydown);         //          // demo         //          this.autoscaledimensions = new system.drawing.sizef(6f, 13f);         this.autoscalemode = system.windows.forms.autoscalemode.font;         this.clientsize = new system.drawing.size(338, 78);         this.controls.add(this.lbltext);         this.controls.add(this.cmbitems);         this.name = "demo";         this.text = "demo";         this.resumelayout(false);         this.performlayout();      }      #endregion      private system.windows.forms.label lbltext;     private combobox cmbitems;      datatable _items = new datatable();      public demo()     {         initializecomponent();          buildlistofitems();     }      private void cmbitems_keydown(object sender, keyeventargs e)     {         if (!e.keycode.equals(keys.enter)) {             if (!cmbitems.droppeddown) {                 cmbitems.droppeddown = true;             }         }         else {             //check text          }          lbltext.text = cmbitems.text;     }      //create demo list of items.     private void buildlistofitems()     {         _items.columns.add("name").datatype = typeof(string);         _items.columns.add("id").datatype = typeof(int);          (int = (int)'a'; < (int)'a' + 26; i++) {             createitem(i, "", 0);         }         cmbitems.datasource = _items;         cmbitems.valuemember = "id";         cmbitems.displaymember = "name";     }      private void createitem(int symbol, string prev, int count)     {         string newprev = string.format("{0}{1}", prev, (char)symbol);         _items.rows.add(newprev, _items.rows.count);         if (count < 4)             createitem(symbol + 1, newprev, ++count);      } } 

i did of on in college , went , checked code. i'm not 100% sure, looking for?

private void combocode_texttype(object sender, eventargs e)     {         int itemsindex = 0;         foreach (string item in cmbgagecode.items)         {             if (item.indexof(cmbgagecode.text) == 0)             {                 cmbgagecode.selectedindex = itemsindex;                 cmbgagecode.select(cmbgagecode.text.length - 1, 0);                 break;             }             itemsindex++;         }     }