/// <summary>
/// Determines if a key exists in an IMFAttributes instance.
/// </summary>
/// <param name="attributes">A valid IMFAttributes instance.</param>
/// <param name="guidKey">The key to test.</param>
/// <returns>True if the instance have a value for the given key ; False otherwise.</returns>
public static bool IsKeyExists(this IMFAttributes attributes, Guid guidKey)
{
if (attributes == null)
{
throw new ArgumentNullException("attributes");
}
HResult hr = attributes.GetItem(guidKey, null);
return(hr != HResult.MF_E_ATTRIBUTENOTFOUND);
}
private static int CopyAttribute(IMFAttributes pSrc, IMFAttributes pDest, Guid key)
{
var variant = new PropVariant();
var hr = pSrc.GetItem(key, variant);
if (Succeeded(hr))
{
hr = pDest.SetItem(key, variant);
}
return(hr);
}
HResult CopyAttribute(IMFAttributes pSrc, IMFAttributes pDest, Guid key)
{
PropVariant var = new PropVariant();
HResult hr = HResult.S_OK;
hr = pSrc.GetItem(key, var);
if (Succeeded(hr))
{
hr = pDest.SetItem(key, var);
}
return(hr);
}
private static MFVideoArea GetArea(IMFAttributes ia, Guid g)
{
PropVariant pv = new PropVariant();
HResult hr = ia.GetItem(g, pv);
if (hr == HResult.MF_E_ATTRIBUTENOTFOUND)
{
return(null);
}
MFError.ThrowExceptionForHR(hr);
return(pv.GetBlob(typeof(MFVideoArea)) as MFVideoArea);
}
public static object GetValue(this IMFAttributes obj, Guid key)
{
if (obj == null)
{
throw new ArgumentNullException(nameof(obj));
}
var pv = new PropVariant();
if (obj.GetItem(key, pv).IsError)
{
return(null);
}
return(pv.Value);
}
public static object GetValue(this IMFAttributes input, Guid key)
{
if (input == null)
{
throw new ArgumentNullException(nameof(input));
}
using (var pv = new PropVariant())
{
if (input.GetItem(key, pv).IsError)
{
return(null);
}
return(pv.Value);
}
}
/// <summary>
/// Retrieves the value associated with a key.
/// </summary>
/// <param name="attributes">A valid IMFAttributes instance.</param>
/// <param name="guidKey">The key that identifies the value to retrieve.</param>
/// <param name="value">The value.</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetItem(this IMFAttributes attributes, Guid guidKey, out object value)
{
if (attributes == null)
{
throw new ArgumentNullException("attributes");
}
HResult hr = 0;
value = null;
using (PropVariant variant = new PropVariant())
{
hr = attributes.GetItem(guidKey, variant);
if (hr.Succeeded())
{
value = variant.GetObject();
}
}
return(hr);
}
int CopyAttribute(IMFAttributes pSrc, IMFAttributes pDest, Guid key)
{
PropVariant var = new PropVariant();
int hr = S_Ok;
hr = pSrc.GetItem(key, var);
if (Succeeded(hr))
{
hr = pDest.SetItem(key, var);
}
return hr;
}
private static int CopyAttribute(IMFAttributes pSrc, IMFAttributes pDest, Guid key)
{
var variant = new PropVariant();
var hr = pSrc.GetItem(key, variant);
if (Succeeded(hr))
hr = pDest.SetItem(key, variant);
return hr;
}
public HResult GetItem(Guid guidKey, PropVariant pValue)
{
return(m_Attribs.GetItem(guidKey, pValue));
}