/// <summary>True if a generic property is available at runtime.</summary>
public static bool HasProperty(ScriptEngine engine, object thisObj, string property)
{
// Exists?
if (thisObj == null)
{
throw new NullReferenceException("Attempted to read property '" + property + "' from a null reference.");
}
// Get the prototype:
Prototype proto = engine.Prototypes.Get(thisObj.GetType());
// Get the property:
return(proto.GetProperty(property) != null);
}
/// <summary>Sets a generic property on the given object at runtime. Note that this can't create a property.</summary>
public static void SetPropertyValue(ScriptEngine engine, object thisObj, string property, object value)
{
// Exists?
if (thisObj == null)
{
throw new NullReferenceException("Attempted to set property '" + property + "' on a null reference.");
}
// Get the prototype:
Prototype proto = engine.Prototypes.Get(thisObj.GetType());
// Get the property:
PropertyVariable pv = proto.GetProperty(property);
if (pv == null)
{
// Undefined:
throw new JavaScriptException(engine, "TypeError", "Can't set dynamic properties on generic objects.");
}
// Set the value:
pv.SetValue(thisObj, value);
}
/// <summary>Pulls a generic property from the given object at runtime.</summary>
public static object GetPropertyValue(ScriptEngine engine, object thisObj, string property)
{
// Exists?
if (thisObj == null)
{
throw new NullReferenceException("Attempted to read property '" + property + "' from a null reference.");
}
// Get the prototype:
Prototype proto = engine.Prototypes.Get(thisObj.GetType());
// Get the property:
PropertyVariable pv = proto.GetProperty(property);
if (pv == null)
{
// Undefined:
return(Nitrassic.Undefined.Value);
}
// Get the value:
return(pv.GetValue(thisObj));
}
internal override void ResolveVariables(OptimizationInfo optimizationInfo)
{
if (ResolvedProperty != null || propertyName != null)
{
// Already resolved.
return;
}
// Resolve kids:
base.ResolveVariables(optimizationInfo);
// Right-hand-side can be a property name (a.b)
if (this.OperatorType == OperatorType.MemberAccess)
{
var rhs = this.GetOperand(1) as NameExpression;
if (rhs == null)
{
throw new JavaScriptException(optimizationInfo.Engine, "SyntaxError", "Invalid member access", 1, optimizationInfo.Source.Path, optimizationInfo.FunctionName);
}
propertyName = rhs.Name;
}
// Or a constant indexer (a['b'])
if (this.OperatorType == OperatorType.Index)
{
var rhs = this.GetOperand(1);
if (rhs != null)
{
Type rhsType = rhs.GetResultType(optimizationInfo);
if (rhsType == typeof(string))
{
// Try a literal:
LiteralExpression literalStr = rhs as LiteralExpression;
if (literalStr != null)
{
propertyName = TypeConverter.ToString(literalStr.Value);
// Could actually be numeric, so try that:
if (propertyName != null && Nitrassic.Library.Array.ParseArrayIndex(propertyName) != uint.MaxValue)
{
// Yep, it is!
isArrayIndex = true;
}
}
}
else if (PrimitiveTypeUtilities.IsNumeric(rhsType))
{
// array index (a[0])
isArrayIndex = true;
}
}
}
if (isArrayIndex == true)
{
// Array indexer
// -------------
// xxx = object[index]
// Load the left-hand side and convert to an object instance.
var lhs = this.GetOperand(0);
// Get the type of the LHS (the object being read from):
Type lhsType = lhs.GetResultType(optimizationInfo);
// Get the proto for it:
Nitrassic.Library.Prototype proto = optimizationInfo.Engine.Prototypes.Get(lhsType);
// Does that type have an indexer method on it? (this[uint])
ResolvedProperty = proto.Indexer(typeof(uint));
if (ResolvedProperty == null)
{
// Try [int] instead:
ResolvedProperty = proto.Indexer(typeof(int));
}
}
if (ResolvedProperty == null && propertyName != null)
{
// Load the left-hand side and convert to an object instance.
var lhs = this.GetOperand(0);
Type lhsType = lhs.GetResultType(optimizationInfo);
// Get the prototype:
Nitrassic.Library.Prototype proto = optimizationInfo.Engine.Prototypes.Get(lhsType);
// Get the property:
ResolvedProperty = proto.GetProperty(propertyName);
if (ResolvedProperty == null)
{
// Add it now (as undefined):
ResolvedProperty = proto.AddProperty(propertyName, null, Nitrassic.Library.PropertyAttributes.FullAccess);
}
}
}