protected T OnGetValue(int index)
{
IndexerValueGetter handler = GetValue;
if (handler != null)
{
return(handler(this, index));
}
throw new ListException("No ValueGetter set.");
}
public ArrayIndexer1(IndexerValueGetter getter)
{
_getter = getter;
}
private static void BuildValueGetters(Expression expression, IList <IValueGetter> list)
{
var memberExpression = expression as MemberExpression;
if (memberExpression == null && expression is UnaryExpression)
{
memberExpression = ((UnaryExpression)expression).Operand as MemberExpression;
}
if (memberExpression != null)
{
var propertyInfo = (PropertyInfo)memberExpression.Member;
list.Add(new PropertyValueGetter(propertyInfo));
if (memberExpression.Expression != null)
{
BuildValueGetters(memberExpression.Expression, list);
}
}
//deals with collection indexers, an indexer [0] will look like a get(0) method call expression
var methodCallExpression = expression as MethodCallExpression;
if (methodCallExpression != null)
{
var methodInfo = methodCallExpression.Method;
Expression argument = methodCallExpression.Arguments.FirstOrDefault();
if (argument == null)
{
var methodValueGetter = new MethodValueGetter(methodInfo, new object[0]);
list.Add(methodValueGetter);
}
else
{
object value;
if (TryEvaluateExpression(argument, out value))
{
var methodValueGetter = new MethodValueGetter(methodInfo, new object[] { value });
list.Add(methodValueGetter);
}
}
if (methodCallExpression.Object != null)
{
BuildValueGetters(methodCallExpression.Object, list);
}
}
if (expression.NodeType == ExpressionType.ArrayIndex)
{
var binaryExpression = (BinaryExpression)expression;
var indexExpression = binaryExpression.Right;
object index;
if (TryEvaluateExpression(indexExpression, out index))
{
var indexValueGetter = new IndexerValueGetter(binaryExpression.Left.Type, (int)index);
list.Add(indexValueGetter);
}
BuildValueGetters(binaryExpression.Left, list);
}
}