Hashtable ht1 = new Hashtable();
ht1.Add("1", "11");
ht1.Add("2", "22");
Hashtable ht2 = new Hashtable();
ht2.Add("3", "33");
ht2.Add("4", "44");
Hashtable ht3 = new Hashtable();
foreach (System.Collections.DictionaryEntry de in ht1)
{
ht3.Add(de.Key, de.Value);
}
foreach (System.Collections.DictionaryEntry de in ht2)
{
ht3.Add(de.Key, de.Value);
}