private void TestAttr()
{
short w1, w2, w3;
short iIndex;
const string v = "ItzaString";
m_head.GetAttributeCountEx(0, out w1);
byte[] b = Encoding.Unicode.GetBytes(v);
m_head.AddAttribute(0, "asdf", out iIndex, AttrDataType.STRING, 0, b, b.Length);
m_head.GetAttributeCountEx(0, out w2);
Debug.Assert(w2 == w1 + 1);
short pNLen = 0;
int pDLen = 0;
AttrDataType pType;
short pLang;
m_head.GetAttributeByIndexEx(0, w1, null, ref pNLen, out pType, out pLang, null, ref pDLen);
byte[] bb = new byte[pDLen];
m_head.GetAttributeByIndexEx(0, w1, null, ref pNLen, out pType, out pLang, bb, ref pDLen);
string ss = Encoding.Unicode.GetString(bb, 0, pDLen - 2);
StringBuilder sbName = new StringBuilder(pNLen);
byte[] bb2 = new byte[pDLen];
m_head.GetAttributeByIndexEx(0, w1, sbName, ref pNLen, out pType, out pLang, bb2, ref pDLen);
Debug.Assert(sbName.ToString() == "asdf" && pType == AttrDataType.STRING && pLang == 0 && v == Encoding.Unicode.GetString(bb2, 0, v.Length * 2));
byte[] wm3 = BitConverter.GetBytes(4144);;
m_head.ModifyAttribute(0, w1, AttrDataType.DWORD, 0, wm3, 4);
byte[] bb4 = new byte[pDLen];
m_head.GetAttributeByIndexEx(0, w1, null, ref pNLen, out pType, out pLang, bb4, ref pDLen);
Debug.Assert(BitConverter.ToInt32(bb4, 0) == 4144);
m_head.DeleteAttribute(0, w1);
m_head.GetAttributeCountEx(0, out w3);
Debug.Assert(w3 == w1);
}
private static MetadataField GetAttributeByIndex(IWMHeaderInfo3 header, int index)
{
StringBuilder attributeName = null;
ushort attributeNameLength = 0;
WMT_ATTR_DATATYPE attributeDataType;
ushort langIndex = 0;
byte[] attributeValue = null;
uint attributeValueLength = 0;
header.GetAttributeByIndexEx(
StreamNumber,
(ushort)index,
attributeName,
ref attributeNameLength,
out attributeDataType,
out langIndex,
attributeValue,
ref attributeValueLength);
attributeName = new StringBuilder(attributeNameLength, attributeNameLength);
attributeValue = new byte[attributeValueLength];
header.GetAttributeByIndexEx(
StreamNumber,
(ushort)index,
attributeName,
ref attributeNameLength,
out attributeDataType,
out langIndex,
attributeValue,
ref attributeValueLength);
object value = ParseAttributeValue(attributeValue, attributeDataType);
MetadataField field = new MetadataField(attributeName.ToString(), value);
return(field);
}