System.Configuration.ConfigurationElement.this C# (CSharp) Метод

        protected internal Object this[ConfigurationProperty prop] {
            get {
                Object o = _values[prop.Name];
                if (o == null) {
                    lock (_values.SyncRoot) {
                        o = _values[prop.Name];
                        if (o == null) {
                            if (typeof(ConfigurationElement).IsAssignableFrom(prop.Type)) {
                                ConfigurationElement childElement = CreateElement(prop.Type);
                                
                                if (_bReadOnly) {
                                    childElement.SetReadOnly();
                                }
                                
                                if (typeof(ConfigurationElementCollection).IsAssignableFrom(prop.Type)) {
                                    ConfigurationElementCollection childElementCollection = childElement as ConfigurationElementCollection;
                                    if (prop.AddElementName != null)
                                        childElementCollection.AddElementName = prop.AddElementName;
                                    if (prop.RemoveElementName != null)
                                        childElementCollection.RemoveElementName = prop.RemoveElementName;
                                    if (prop.ClearElementName != null)
                                        childElementCollection.ClearElementName = prop.ClearElementName;
                                }

                                //_values[prop.Name] = childElement;
                                _values.SetValue(prop.Name, childElement, ConfigurationValueFlags.Inherited, null);
                                o = childElement;
                            }
                            else {
                                o = prop.DefaultValue;
                            }
                        }
                    }
                }
                else if (o == s_nullPropertyValue) {
                    o = null;
                }

                // If its an invalid value - throw the error now
                if (o is InvalidPropValue) {
                    throw ((InvalidPropValue)o).Error;
                }

                return o;
            }

            set {
                SetPropertyValue(prop, value,false); // Do not ignore locks!!!
            }
        }