public virtual DCMAbstractType Decode(byte[] data, ref uint idx)
{
DCMDataElement element = new DCMDataElement();
//vrdecoder = new US(this);
//读取TAG
element.gtag = vrdecoder.GetUShort(data, ref idx);
element.etag = vrdecoder.GetUShort(data, ref idx);
if (element.gtag == 0xfffe && element.etag == 0xe000) //处理SQ的三个特殊标记
{
DCMDataItem sqitem = new DCMDataItem(this);
uint length = vrdecoder.GetUInt(data, ref idx); //不能用GetLength
uint offset = idx;
while (idx - offset < length)
{
DCMAbstractType sqelem = Decode(data, ref idx); //递归
if (length == 0xffffffff && sqelem.gtag == 0xfffe && sqelem.etag == 0xe00d) //条目结束标记
{
break;
}
sqitem.items.Add(sqelem);
}
return(sqitem);
}
else if (element.gtag == 0xfffe && element.etag == 0xe0dd) //序列结束标记
{
element.vr = "UL";
element.length = vrdecoder.GetUInt(data, ref idx); //不能用GetLength
return(element);
}
//查数据字典得到VR,Name,VM
element.vr = vrdecoder.GetVR(data, ref idx);
DicomDictionaryEntry entry = dictionary.GetEntry(element.gtag, element.etag);
if (entry != null)
{
if (element.vr == "")
{
element.vr = entry.VR;
}
element.name = entry.Keyword;
element.vm = entry.VM;
}
else if (element.vr == "" && element.etag == 0)
{
element.vr = "US";
}
//根据得到的VR实例化具体vr类，此处暂时用vrdecode(即US类对象)
element.vrparser = vrfactory.GetVR(element.vr);
vrdecoder = element.vrparser;
//读取值长度
element.length = vrdecoder.GetLength(data, ref idx);
//读取值
element.value = vrdecoder.GetValue(data, ref idx, element.length);
return(element);
}
public virtual List <DCMAbstractType> Decode(byte[] data, ref uint idx) //解码方法
{
while (idx < data.Length)
{
DCMAbstractType item = null;
item = syntax.Decode(data, ref idx);//根据传入的传输语法
items.Add(item);
}
return(items);
}
public override byte[] GetValue(byte[] data, ref uint idx, uint length)
{
uint offset = idx;
DCMDataSequence sq = new DCMDataSequence(syntax);
while (idx - offset < length)
{
DCMAbstractType item = syntax.Decode(data, ref idx);
if (length == 0xffffffff && item.gtag == 0xfffe && item.etag == 0xe0dd)
{
break;
}
else
{
sq.items.Add((DCMDataItem)item);
}
}
GCHandle handle = GCHandle.Alloc(sq);
IntPtr ptr = GCHandle.ToIntPtr(handle);
return(BitConverter.GetBytes(ptr.ToInt64()));
}
