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Actually, .NET Framework already has the needed code for spliting. Let's see how:
foreach(object o in dropDownList.Items) {string[] splitted = o.ToString().Split(newchar[]{' '});//split by ' '(space)foreach(string s in splitted) dropDownList2.Items.Add(s);//add them to another drop down }
Hope this helps.
Sincerely,
Yasser
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