class CredentialList : ICredentials
{
    class CredentialInfo
    {
        public Uri uriObj;
        public String authenticationType;
        public NetworkCredential networkCredentialObj;
  
        public CredentialInfo(Uri uriObj, String authenticationType, NetworkCredential networkCredentialObj)
        {
            this.uriObj = uriObj;
            this.authenticationType = authenticationType;
            this.networkCredentialObj = networkCredentialObj;
        }
    }

    private ArrayList arrayListObj;

    public CredentialList()
    {
        arrayListObj = new ArrayList();
    }

    public void Add (Uri uriObj, String authenticationType, NetworkCredential credential)
    {
        // Add a 'CredentialInfo' object into a list.
        arrayListObj.Add (new CredentialInfo(uriObj, authenticationType, credential));      
    }
    // Remove the 'CredentialInfo' object from the list that matches to the given 'Uri' and 'AuthenticationType'
    public void Remove (Uri uriObj, String authenticationType)
    {
        for(int index=0;index < arrayListObj.Count; index++)
        {
            CredentialInfo credentialInfo = (CredentialInfo)arrayListObj[index];
            if(uriObj.Equals(credentialInfo.uriObj)&& authenticationType.Equals(credentialInfo.authenticationType))
                arrayListObj.RemoveAt(index);
        }
    }
    public NetworkCredential GetCredential (Uri uriObj, String authenticationType)
    {
        for(int index=0;index < arrayListObj.Count; index++)
        {
            CredentialInfo credentialInfoObj = (CredentialInfo)arrayListObj[index];
            if(uriObj.Equals(credentialInfoObj.uriObj) && authenticationType.Equals(credentialInfoObj.authenticationType))
                return credentialInfoObj.networkCredentialObj;
        }
        return null;
    }
};