c#自定义配置节点（web.config、app.config）

这里提供一个实例的完整写法，深入了解的话请参考官方的文档

1.项目引用System.Configuration

2.编写PositionConfigurationSection，代码如下：

public class PositionConfigurationSection: ConfigurationSection
    {
        [ConfigurationProperty("Positions", IsRequired =true)]
        [ConfigurationCollection(typeof(PositionSection),CollectionType =ConfigurationElementCollectionType.AddRemoveClearMap,AddItemName ="Position")]
        public PositionContainer Positions
        {
            get => base["Positions"] as PositionContainer;
            set => base["Positions"] = value;
        }
    }

3.编写PositionContainer：

 public class PositionContainer : ConfigurationElementCollection
    {
        protected override ConfigurationElement CreateNewElement()
        {
            return new PositionSection();
        }

        protected override object GetElementKey(ConfigurationElement element)
        {
            return (element as PositionSection).ID;
        }
    }

4.编写PositionSection：

  public class PositionSection: ConfigurationElement
    {
        [ConfigurationProperty("ID", IsRequired = true)]
        public int ID
  &nb