The NameValueCollection sets more than one value for a single key. Now let us see how to use them in our C# program.
Set the collection −
static NameValueCollection GetCollection() {
NameValueCollection myCollection = new NameValueCollection();
myCollection.Add("Tim", "One");
myCollection.Add("John", "Two");
myCollection.Add("Jamie", "Three");
return myCollection;
}Now with the GetCollection() method use the “AllKeys” method property to display all the keys −
NameValueCollection myCollection = GetCollection();
foreach (string key in myCollection.AllKeys) {
Console.WriteLine(key);
}