How to swap Hashtable's key with Value.

Accepted answer

You could do it slightly simpler using an additional array and the CopyTo method rather than 2 lists but without creating an additional HashTable as follows:

using System;

using System.Collections;

class Program

{

static void Main()

{

Hashtable hsTbl = new Hashtable();

hsTbl.Add(1, "Suhas");

hsTbl.Add(2, "Madhuri");

hsTbl.Add(3, "Om");

DictionaryEntry[] entries = new DictionaryEntry[hsTbl.Count];

hsTbl.CopyTo(entries, 0);

hsTbl.Clear();

foreach(DictionaryEntry de in entries) hsTbl.Add(de.Value, de.Key);

// check it worked

foreach(DictionaryEntry de in hsTbl)

{

Console.WriteLine("{0} : {1}", de.Key, de.Value);

}

Note that, in general, no method is guaranteed to work because some of the values in the original hashtable may be duplicated and therefore be unsuitable as keys.

0

Suhas D13y ago

@Vulpes :Yes, This is more closer to answer and acceptable.

@Santhosh Kumar : Your approch is also right but I did want to create new Hashtable for this.

0

Santhosh Kumar Jayaraman13y ago

You can try this one also. Creating another hashtable and adding values to it from existing one

Hashtable hsTbl = new Hashtable();

hsTbl.Add(1, "Suhas");

hsTbl.Add(2, "Madhuri");

hsTbl.Add(3, "Om");

IDictionaryEnumerator myEnumerator = hsTbl.GetEnumerator();

Hashtable hstbl2 = new Hashtable();

while (myEnumerator.MoveNext())

{

hstbl2.Add(myEnumerator.Value, myEnumerator.Key);

}

0