/// <summary>
/// Tries to set a named property or field
/// </summary>
/// <param name="luaState"></param>
/// <param name="targetType"></param>
/// <param name="target"></param>
/// <param name="bindingType"></param>
/// <returns>false if unable to find the named member, true for success</returns>
bool TrySetMember (LuaState luaState, ProxyType targetType, object target, BindingFlags bindingType, out string detailMessage)
{
detailMessage = null; // No error yet
// If not already a string just return - we don't want to call tostring - which has the side effect of
// changing the lua typecode to string
// Note: We don't use isstring because the standard lua C isstring considers either strings or numbers to
// be true for isstring.
if (LuaLib.LuaType (luaState, 2) != LuaTypes.String) {
detailMessage = "property names must be strings";
return false;
}
// We only look up property names by string
string fieldName = LuaLib.LuaToString (luaState, 2).ToString ();
if (fieldName == null || fieldName.Length < 1 || !(char.IsLetter (fieldName [0]) || fieldName [0] == '_')) {
detailMessage = "invalid property name";
return false;
}
// Find our member via reflection or the cache
var member = (MemberInfo)CheckMemberCache (memberCache, targetType, fieldName);
if (member == null) {
var members = targetType.GetMember (fieldName, bindingType | BindingFlags.Public);
if (members.Length > 0) {
member = members [0];
SetMemberCache (memberCache, targetType, fieldName, member);
} else {
detailMessage = "field or property '" + fieldName + "' does not exist";
return false;
}
}
#if NETFX_CORE
if (member is FieldInfo) {
#else
if (member.MemberType == MemberTypes.Field) {
#endif
var field = (FieldInfo)member;
object val = translator.GetAsType (luaState, 3, field.FieldType);
try {
field.SetValue (target, val);
} catch (Exception e) {
ThrowError (luaState, e);
}
// We did a call
return true;
#if NETFX_CORE
} else if (member is PropertyInfo) {
#else
} else if (member.MemberType == MemberTypes.Property) {
#endif
var property = (PropertyInfo)member;
object val = translator.GetAsType (luaState, 3, property.PropertyType);
try {
property.SetValue (target, val, null);
} catch (Exception e) {
ThrowError (luaState, e);
}
// We did a call
return true;
}
detailMessage = "'" + fieldName + "' is not a .net field or property";
return false;
}
/*
* Writes to fields or properties, either static or instance. Throws an error
* if the operation is invalid.
*/
private int SetMember (LuaState luaState, ProxyType targetType, object target, BindingFlags bindingType)
{
string detail;
bool success = TrySetMember (luaState, targetType, target, bindingType, out detail);
if (!success)
translator.ThrowError (luaState, detail);
return 0;
}
/// <summary>
/// Convert a C# exception into a Lua error
/// </summary>
/// <param name="e"></param>
/// We try to look into the exception to give the most meaningful description
void ThrowError (LuaState luaState, Exception e)
{
// If we got inside a reflection show what really happened
var te = e as TargetInvocationException;
if (te != null)
e = te.InnerException;
translator.ThrowError (luaState, e);
}
/// <summary>
/// Does this method exist as either an instance or static?
/// </summary>
/// <param name="objType"></param>
/// <param name="methodName"></param>
/// <returns></returns>
bool IsMemberPresent (ProxyType objType, string methodName)
{
object cachedMember = CheckMemberCache (memberCache, objType, methodName);
if (cachedMember != null)
return true;
var members = objType.GetMember (methodName, BindingFlags.Static | BindingFlags.Instance | BindingFlags.Public);
return (members.Length > 0);
}
/*
* Pushes the value of a member or a delegate to call it, depending on the type of
* the member. Works with static or instance members.
* Uses reflection to find members, and stores the reflected MemberInfo object in
* a cache (indexed by the type of the object and the name of the member).
*/
int GetMember (LuaState luaState, ProxyType objType, object obj, string methodName, BindingFlags bindingType)
{
bool implicitStatic = false;
MemberInfo member = null;
object cachedMember = CheckMemberCache (memberCache, objType, methodName);
if (cachedMember is LuaNativeFunction) {
translator.PushFunction (luaState, (LuaNativeFunction)cachedMember);
translator.Push (luaState, true);
return 2;
} else if (cachedMember != null)
member = (MemberInfo)cachedMember;
else {
var members = objType.GetMember (methodName, bindingType | BindingFlags.Public);
if (members.Length > 0)
member = members [0];
else {
// If we can't find any suitable instance members, try to find them as statics - but we only want to allow implicit static
members = objType.GetMember (methodName, bindingType | BindingFlags.Static | BindingFlags.Public);
if (members.Length > 0) {
member = members [0];
implicitStatic = true;
}
}
}
if (member != null) {
#if NETFX_CORE
if (member is FieldInfo) {
#else
if (member.MemberType == MemberTypes.Field) {
#endif
var field = (FieldInfo)member;
if (cachedMember == null)
SetMemberCache (memberCache, objType, methodName, member);
try {
var value = field.GetValue (obj);
translator.Push (luaState, value);
} catch {
LuaLib.LuaPushNil (luaState);
}
#if NETFX_CORE
} else if (member is PropertyInfo) {
#else
} else if (member.MemberType == MemberTypes.Property) {
#endif
var property = (PropertyInfo)member;
if (cachedMember == null)
SetMemberCache (memberCache, objType, methodName, member);
try {
object value = property.GetValue (obj, null);
translator.Push (luaState, value);
} catch (ArgumentException) {
// If we can't find the getter in our class, recurse up to the base class and see
// if they can help.
if (objType.UnderlyingSystemType != typeof(object))
#if NETFX_CORE
return GetMember (luaState, new ProxyType(objType.UnderlyingSystemType.GetTypeInfo().BaseType), obj, methodName, bindingType);
#else
return GetMember (luaState, new ProxyType(objType.UnderlyingSystemType.BaseType), obj, methodName, bindingType);
#endif
else
LuaLib.LuaPushNil (luaState);
} catch (TargetInvocationException e) { // Convert this exception into a Lua error
ThrowError (luaState, e);
LuaLib.LuaPushNil (luaState);
}
#if NETFX_CORE
} else if (member is EventInfo) {
#else
} else if (member.MemberType == MemberTypes.Event) {
#endif
var eventInfo = (EventInfo)member;
if (cachedMember == null)
SetMemberCache (memberCache, objType, methodName, member);
translator.Push (luaState, new RegisterEventHandler (translator.pendingEvents, obj, eventInfo));
} else if (!implicitStatic) {
#if NETFX_CORE
var typeInfo = member as TypeInfo;
if (typeInfo != null && !typeInfo.IsPublic && !typeInfo.IsNotPublic) {
#else
if (member.MemberType == MemberTypes.NestedType) {
#endif
// kevinh - added support for finding nested types-
// cache us
if (cachedMember == null)
SetMemberCache (memberCache, objType, methodName, member);
// Find the name of our class
string name = member.Name;
var dectype = member.DeclaringType;
// Build a new long name and try to find the type by name
string longname = dectype.FullName + "+" + name;
var nestedType = translator.FindType (longname);
translator.PushType (luaState, nestedType);
} else {
// Member type must be 'method'
var wrapper = new LuaNativeFunction ((new LuaMethodWrapper (translator, objType, methodName, bindingType)).invokeFunction);
if (cachedMember == null)
SetMemberCache (memberCache, objType, methodName, wrapper);
translator.PushFunction (luaState, wrapper);
translator.Push (luaState, true);
return 2;
}
} else {
// If we reach this point we found a static method, but can't use it in this context because the user passed in an instance
translator.ThrowError (luaState, "can't pass instance to static method " + methodName);
LuaLib.LuaPushNil (luaState);
}
} else {
if (objType.UnderlyingSystemType != typeof(object)) {
#if NETFX_CORE
return GetMember (luaState, new ProxyType(objType.UnderlyingSystemType.GetTypeInfo().BaseType), obj, methodName, bindingType);
#else
return GetMember (luaState, new ProxyType(objType.UnderlyingSystemType.BaseType), obj, methodName, bindingType);
#endif
}
// kevinh - we want to throw an exception because meerly returning 'nil' in this case
// is not sufficient. valid data members may return nil and therefore there must be some
// way to know the member just doesn't exist.
translator.ThrowError (luaState, "unknown member name " + methodName);
LuaLib.LuaPushNil (luaState);
}
// push false because we are NOT returning a function (see luaIndexFunction)
translator.Push (luaState, false);
return 2;
}
/// <summary>
/// Tries to set a named property or field
/// </summary>
/// <param name="luaState"></param>
/// <param name="targetType"></param>
/// <param name="target"></param>
/// <param name="bindingType"></param>
/// <returns>false if unable to find the named member, true for success</returns>
bool TrySetMember (LuaState luaState, ProxyType targetType, object target, BindingFlags bindingType, out string detailMessage)
{
detailMessage = null; // No error yet
// If not already a string just return - we don't want to call tostring - which has the side effect of
// changing the lua typecode to string
// Note: We don't use isstring because the standard lua C isstring considers either strings or numbers to
// be true for isstring.
if (LuaLib.LuaType (luaState, 2) != LuaTypes.String) {
detailMessage = "property names must be strings";
return false;
}
// We only look up property names by string
string fieldName = LuaLib.LuaToString (luaState, 2).ToString ();
if (fieldName == null || fieldName.Length < 1 || !(char.IsLetter (fieldName [0]) || fieldName [0] == '_')) {
detailMessage = "invalid property name";
return false;
}
// Find our member via reflection or the cache
var member = (MemberInfo)CheckMemberCache (memberCache, targetType, fieldName);
if (member == null) {
var members = targetType.GetMember (fieldName, bindingType | BindingFlags.Public);
if (members.Length > 0) {
member = members [0];
SetMemberCache (memberCache, targetType, fieldName, member);
} else {
detailMessage = "field or property '" + fieldName + "' does not exist";
return false;
}
}
if (member.MemberType == MemberTypes.Field) {
var field = (FieldInfo)member;
object val = translator.GetAsType (luaState, 3, field.FieldType);
try {
field.SetValue (target, val);
} catch (Exception e) {
ThrowError (luaState, e);
}
// We did a call
return true;
} else if (member.MemberType == MemberTypes.Property) {
var property = (PropertyInfo)member;
object val = translator.GetAsType (luaState, 3, property.PropertyType);
try {
property.SetValue (target, val, null);
} catch (Exception e) {
ThrowError (luaState, e);
}
// We did a call
return true;
}
detailMessage = "'" + fieldName + "' is not a .net field or property";
return false;
}
