It's not difficult.
You just call "Item" property.
Sample Code:
==================
Type aType = hasIndexerObject.GetType();
PropertyInfo pi = aType.PetProperty("Item", typeof(object), new Type[] { typeof(string) });
if (pi != null) {
// call indexter property.
object retValue = pi.GetValue(hasIndexerObject, new object[] { param });
} else {
// this class didn't have an indexer.
}
==================
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