c# - ListBox Items Disappear -

i have listbox (called waferslistbox) bounded arraylist of object type (called wafers). when want add listbox dynamically, use following code:

waferslistbox.datasource = null; waferslistbox.datasource = wafers; waferslistbox.refresh(); 

this changes items in listbox, of items disappear (they're still there , can selected, user can't see them).

any ideas on how fix this?

update: wafer class:

public class wafer {     public string maid;      public string mid     {                 {             return maid;         }         set         {             maid = value;         }     }      public wafer(string m)     {         maid = m;     } } 

this code call, adds copy of selected item listbox:

wafer w = waferslistbox.selecteditem wafer; wafers.add(w);            waferslistbox.datasource = null; waferslistbox.displaymember = "mid"; waferslistbox.datasource = wafers; waferslistbox.refresh(); 

you should tell waferslistbox property use it's caption.

do this;

waferslistbox.displaymember = "propertynamethatyouwanttoshow";