/// <summary>
/// Search an occurence of pathPos in list. The string pathPos should have following layout: "x,yy" where
/// x = a number greater then 0 e.g. 2
/// yy = a tag name e.g. 30
/// The list is searched for the given tag (case insensitive). The list can have multiple tags with the same name; the number
/// indicates which entry has to be returned
/// </summary>
/// <param name="list">A list TLV items</param>
/// <param name="posCommaTagName">The entry to search for example "1,6F"</param>
/// <returns>The index in the list that contains the entry or -1 if not found</returns>
private int searchOccurence(TLVList list, string posCommaTagName)
{
if (list == null)
{
throw new ArgumentNullException("list");
}
if (string.IsNullOrEmpty(posCommaTagName))
{
throw new ArgumentException("pathPos should not be null or empty", "pathPos");
}
string[] pathPosSplitted = posCommaTagName.Split(new char[] { ',' });
if (pathPosSplitted.Length != 2)
{
throw new ArgumentException(string.Format("Invalid pathPos: {0}", posCommaTagName));
}
int occurence = int.Parse(pathPosSplitted[0]);
if (occurence < 1)
{
throw new ArgumentException(string.Format("Invalid position: {0}", occurence));
}
string TagName = pathPosSplitted[1];
if (string.IsNullOrEmpty(TagName))
{
throw new ArgumentException(string.Format("Invalid tagname: {0}", TagName));
}
bool found = false;
int i = 0;
int occurencesFound = 0;
while (!found && i < list.Count)
{
if (string.Compare(list[i].TagName, TagName, true) == 0)
{
occurencesFound++;
}
if (occurencesFound == occurence)
{
return(i);
}
i++;
}
return(-1);
}
private static byte CONSTRUCTED_DATAOBJECT_MASK = 0x20; // 0010 0000 (Object primitive or constructed)
public static TLVList Parse(Stream s)
{
TLVList l = new TLVList();
while (s.Position < s.Length)
{
TLV t = new TLV(s);
t.Childs = TLV.ParseTagList(t.Value);
l.Add(t);
}
return(l);
}
/// <summary>
/// Retrieve the TLV structure at the given path. A path is for example "1,6F|2,30|1,31|1,04"
/// </summary>
/// <param name="path">The path to follow</param>
/// <returns>The TLV structure at the given path if found; null otherwise</returns>
public TLV getTag(string path)
{
if (string.IsNullOrEmpty(path))
{
throw new ArgumentException("Path should not be null or empty", "path");
}
string[] pathParts = path.Split(new char[] { '|' });
int depth = 0;
bool found = false;
TLVList currentList = this;
while (!found && depth < pathParts.Length)
{
int pos = searchOccurence(currentList, pathParts[depth]);
if (pos < 0)
{
// Tag not found at current level
return(null);
}
// Tag is found, but are we at desired level?
if (depth == pathParts.Length - 1)
{
// Yes; return this entry
return(currentList[pos]);
}
else if (currentList[pos].Childs != null)
{
// Not yet at desired level => go down
currentList = currentList[pos].Childs;
found = false;
depth++;
}
else
{
// Not at desired level AND current level does not have any childs....
return(null);
}
}
// Not found
return(null);
}
private static TLVList ParseTagList(byte[] data)
{
TLVList tagList = new TLVList();
MemoryStream ms = new MemoryStream(data);
while (ms.Position < ms.Length)
{
TLV tlv = new TLV(ms);
if (tlv.Value != null && tlv.Value.Length > 0)
{
if (tlv.isConstructed)
{
tlv.Childs = TLV.ParseTagList(tlv.Value);
}
tagList.Add(tlv);
}
}
return(tagList);
}
