private void EnsureConverter(Type sourceType, Type targetType)
{
if (this.sourceType != sourceType || this.targetType != targetType)
{
this.converter = DefaultValueConverter.Create(sourceType, targetType, this.targetToSourceNeeded);
this.sourceType = sourceType;
this.targetType = targetType;
}
}
internal static IValueConverter Create(Type sourceType, Type targetType, bool targetToSource)
{
if (targetType == typeof(object))
{
return(new ObjectTargetConverter(sourceType));
}
if (sourceType == typeof(object))
{
return(new ObjectSourceConverter(targetType));
}
if (SystemConvertConverter.CanConvert(sourceType, targetType))
{
return(new SystemConvertConverter(sourceType, targetType));
}
Type underlyingType = Nullable.GetUnderlyingType(sourceType);
if (underlyingType != null)
{
sourceType = underlyingType;
return(DefaultValueConverter.Create(sourceType, targetType, targetToSource));
}
underlyingType = Nullable.GetUnderlyingType(targetType);
if (underlyingType != null)
{
targetType = underlyingType;
return(DefaultValueConverter.Create(sourceType, targetType, targetToSource));
}
if (sourceType.IsInterface || targetType.IsInterface)
{
return(new InterfaceConverter(sourceType, targetType));
}
TypeConverter converter = DefaultValueConverter.GetConverter(sourceType);
bool canConvertTo = converter != null?converter.CanConvertTo(targetType) : false;
bool canConvertFrom = converter != null?converter.CanConvertFrom(targetType) : false;
if ((canConvertTo || targetType.IsAssignableFrom(sourceType)) && (!targetToSource || canConvertFrom || sourceType.IsAssignableFrom(targetType)))
{
return(new SourceDefaultValueConverter(converter, sourceType, targetType, !targetToSource ? false : canConvertFrom, canConvertTo));
}
converter = DefaultValueConverter.GetConverter(targetType);
canConvertTo = converter != null?converter.CanConvertTo(sourceType) : false;
canConvertFrom = converter != null?converter.CanConvertFrom(sourceType) : false;
if ((!canConvertFrom && !targetType.IsAssignableFrom(sourceType)) || (targetToSource && !canConvertTo && !sourceType.IsAssignableFrom(targetType)))
{
CultureInfo invariantCulture = CultureInfo.InvariantCulture;
string str = "ValueConverter can't convert Type {0} to Type {1}";
object[] objArray = new object[] { sourceType.ToString(), targetType.ToString() };
throw new InvalidOperationException(string.Format(invariantCulture, str, objArray));
}
return(new TargetDefaultValueConverter(converter, sourceType, targetType, canConvertFrom, !targetToSource ? false : canConvertTo));
}
