| private SetConstant ( object defaultValue ) : void | ||
| defaultValue | object | |
| Результат | void | |
private void Visit(IParameterDefinition parameterDefinition, ParameterBuilder parameterBuilder) {
if (parameterDefinition.HasDefaultValue) {
parameterDefinition.DefaultValue.Dispatch(this);
parameterBuilder.SetConstant(this.value);
}
foreach (var customAttribute in parameterDefinition.Attributes) {
var customAttributeBuilder = this.GetCustomAttributeBuilder(customAttribute);
parameterBuilder.SetCustomAttribute(customAttributeBuilder);
}
if (parameterDefinition.IsMarshalledExplicitly)
parameterBuilder.SetCustomAttribute(GetMarshalAsAttribute(parameterDefinition.MarshallingInformation));
}
public static void CopyParameterAttributes(ParameterInfo from, ParameterBuilder to) {
if (from.IsDefined(typeof(ParamArrayAttribute), false)) {
to.SetCustomAttribute(new CustomAttributeBuilder(
typeof(ParamArrayAttribute).GetConstructor(Type.EmptyTypes), ArrayUtils.EmptyObjects)
);
} else if (from.IsDefined(typeof(ParamDictionaryAttribute), false)) {
to.SetCustomAttribute(new CustomAttributeBuilder(
typeof(ParamDictionaryAttribute).GetConstructor(Type.EmptyTypes), ArrayUtils.EmptyObjects)
);
}
if ((from.Attributes & ParameterAttributes.HasDefault) != 0) {
to.SetConstant(from.DefaultValue);
}
}
/// <summary>
/// Provide implementation for setting default value
/// </summary>
private static void SetDefaultValueInternal(IntPtr ipVariant, Type type, ParameterBuilder paramBuilder, FieldBuilder fieldBuilder, short typeVt)
{
if (type == null) throw new ArgumentNullException(nameof(type));
// Use the element type for normalization if the type is a ByRef
while (type.IsByRef)
type = type.GetElementType();
short defaultValueVt = Marshal.ReadInt16(ipVariant);
object defaultValue = GetNormalizedDefaultValueFromVariant(ipVariant, type, defaultValueVt, typeVt);
if (type.IsEnum && (defaultValueVt == (short)VarEnum.VT_I4 || defaultValueVt == (short)VarEnum.VT_UI4))
{
// 1) I can't dynamically create the enum in a ReflectionOnlyContext
// 2) In pre-4.0, SetConstant(1) won't work for enum types.
// After talking with team members we decided that this is a minor functionality that
// we can live without in pre-4.0
// return;
}
// Currently ParameterBuilder.SetConstant doesn't emit the custom attributes so certain types of constants
// so we need to do that by ourselves
CustomAttributeBuilder builder = null;
if (type == typeof(Decimal))
{
DECIMAL realDecimal;
IntPtr pDecimal = IntPtr.Zero;
// Unfortunate we cannot directly access the fields in the decimal struct and we need to rely on the fact
// that the internal representation of decimal & DECIMAL are the same, which will most likely remain true in the future
// because CLR internally does the same thing
Debug.Assert(sizeof(decimal) == Marshal.SizeOf(typeof(DECIMAL)));
try
{
pDecimal = Marshal.AllocCoTaskMem(sizeof(decimal));
// We convert it to unmanaged then back to managed to avoid unsafe code, so that we won't crash immediately in partial trust
Marshal.StructureToPtr(defaultValue, pDecimal, false);
realDecimal = (DECIMAL)Marshal.PtrToStructure(pDecimal, typeof(DECIMAL));
}
finally
{
if (pDecimal != IntPtr.Zero)
Marshal.FreeCoTaskMem(pDecimal);
}
builder = CustomAttributeHelper.GetBuilderForDecimalConstant(
realDecimal.scale,
realDecimal.sign,
realDecimal.hi32,
realDecimal.mid32,
realDecimal.low32);
}
else if (type == typeof(DateTime) && defaultValueVt == (short)VarEnum.VT_DATE)
{
builder = CustomAttributeHelper.GetBuilderForDateTimeConstant(((DateTime)defaultValue).Ticks);
}
else if (defaultValueVt == (short)VarEnum.VT_UNKNOWN)
{
// Currently ParameterBuilder.SetConstant doesn't emit the IUnknownConstantAttribute
// for IUnknown so we need to do that by ourselves
builder = CustomAttributeHelper.GetBuilderForIUnknownConstant();
}
else if (defaultValueVt == (short)VarEnum.VT_DISPATCH)
{
// Currently ParameterBuilder.SetConstant doesn't emit the IDispatchConstantAttribute
// for IDispatch so we need to do that by ourselves
builder = CustomAttributeHelper.GetBuilderForIDispatchConstant();
}
if (builder != null)
{
if (paramBuilder != null)
paramBuilder.SetCustomAttribute(builder);
if (fieldBuilder != null)
fieldBuilder.SetCustomAttribute(builder);
}
else
{
try
{
if (paramBuilder != null)
paramBuilder.SetConstant(defaultValue);
if (fieldBuilder != null)
fieldBuilder.SetConstant(defaultValue);
}
catch (Exception)
{
// Debug.Assert(type.IsEnum, "We should avoid failing for non-Enum default values");
}
}
}