/// <summary>
/// Find the face closest to the specified style, weight and stretch.
/// Returns null if there is no matching face.
/// </summary>
private FamilyTypeface FindNearestFamilyTypeface(
FontStyle style,
FontWeight weight,
FontStretch stretch
)
{
if (_fontInfo.FamilyTypefaces == null || _fontInfo.FamilyTypefaces.Count == 0)
{
return(null);
}
FamilyTypeface bestFace = (FamilyTypeface)_fontInfo.FamilyTypefaces[0];
MatchingStyle bestMatch = new MatchingStyle(bestFace.Style, bestFace.Weight, bestFace.Stretch);
MatchingStyle target = new MatchingStyle(style, weight, stretch);
for (int i = 1; i < _fontInfo.FamilyTypefaces.Count; i++)
{
FamilyTypeface currentFace = (FamilyTypeface)_fontInfo.FamilyTypefaces[i];
MatchingStyle currentMatch = new MatchingStyle(currentFace.Style, currentFace.Weight, currentFace.Stretch);
if (MatchingStyle.IsBetterMatch(target, bestMatch, ref currentMatch))
{
bestFace = currentFace;
bestMatch = currentMatch;
}
}
return(bestFace);
}
/// <summary>
/// Find the face exactly matching the specified style, weight and stretch.
/// Returns null if there is no matching face.
/// </summary>
private FamilyTypeface FindExactFamilyTypeface(
FontStyle style,
FontWeight weight,
FontStretch stretch
)
{
if (_fontInfo.FamilyTypefaces == null || _fontInfo.FamilyTypefaces.Count == 0)
{
return(null);
}
MatchingStyle target = new MatchingStyle(style, weight, stretch);
foreach (FamilyTypeface currentFace in _fontInfo.FamilyTypefaces)
{
MatchingStyle currentMatch = new MatchingStyle(currentFace.Style, currentFace.Weight, currentFace.Stretch);
if (currentMatch == target)
{
return(currentFace);
}
}
return(null);
}
/// <summary>
/// Finds the best match among the candidates.
/// </summary>
/// <param name="binder">The binder that is requesting the match.</param>
/// <param name="args">The args passed in to the invocation.</param>
/// <param name="genericArgs">The generic args if any.</param>
/// <param name="candidates">The candidate methods to use for the match..</param>
/// <param name="matching">if set to <c>MatchingStyle.AssignableFrom</c>, uses a more lax matching approach for arguments, with IsAssignableFrom instead of == for arg type,
/// and <c>MatchingStyle.GenericTypeHint</c> tries to use the generic arguments as type hints if they match the # of args.</param>
private IInvocable FindBestMatchImpl(DynamicMetaObjectBinder binder, object[] args, List <Type> genericArgs, IEnumerable <IInvocable> candidates, MatchingStyle matching)
{
dynamic dynamicBinder = binder.AsDynamicReflection();
for (int i = 0; i < args.Length; i++)
{
var index = i;
if (args[index] != null)
{
switch (matching)
{
case MatchingStyle.ExactType:
candidates = candidates.Where(x => x.Parameters[index].ParameterType.IsAssignableFrom(GetArgumentType(args[index])));
break;
case MatchingStyle.AssignableFrom:
candidates = candidates.Where(x => x.Parameters[index].ParameterType.IsEquivalentTo(GetArgumentType(args[index])));
break;
case MatchingStyle.ExactTypeGenericHint:
candidates = candidates.Where(x => x.Parameters.Count == genericArgs.Count &&
x.Parameters[index].ParameterType.IsEquivalentTo(genericArgs[index]));
break;
case MatchingStyle.AssignableFromGenericHint:
candidates = candidates.Where(x => x.Parameters.Count == genericArgs.Count &&
x.Parameters[index].ParameterType.IsAssignableFrom(genericArgs[index]));
break;
default:
break;
}
}
IEnumerable enumerable = dynamicBinder.ArgumentInfo;
// The binder has the extra argument info for the "this" parameter at the beginning.
if (enumerable.Cast <object>().ToList()[index + 1].AsDynamicReflection().IsByRef)
{
candidates = candidates.Where(x => x.Parameters[index].ParameterType.IsByRef);
}
// Only filter by matching generic argument count if the generics isn't being used as parameter type hints.
if (genericArgs.Count > 0 && matching != MatchingStyle.AssignableFromGenericHint && matching != MatchingStyle.ExactTypeGenericHint)
{
candidates = candidates.Where(x => x.IsGeneric && x.GenericParameters == genericArgs.Count);
}
}
return(candidates.FirstOrDefault());
}
