CallerMemberName如何工作？ [英] How CallerMemberName works?

问题描述

我见过一些使用[CallerMemberName]作为方法参数前缀的INotifyPropertyChanged成员方法。我想知道它是如何工作的。怎么做一些类似的呢？请问任何人解释一下吗？



注：

我已经读过一些链接 [ ^ ]我们可以在其中找到一些额外的改进。 net4.5关于属性使用。请告诉我一些与此类似的链接:)



我的自定义属性类

Hi,

i have seen some of the INotifyPropertyChanged member method using [CallerMemberName] as a method argument prefix. i want to know how actually it works. how to do some this similar to it? can any one explain me please?

Note:
I have already read some of the links [^]where we can find some additional improvements in .net4.5 regarding attribute usage. please let me know some links other than similar to this :)

My Custom attribute class

namespace AttributeTesting
{
    [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
    public class CallerMember : Attribute
    {
public string ParameterName { get; set; }
    }
}

已实施employeeClass

Implemented employeeClass

namespace AttributeTesting.Data
{
    [CallerMember]    
public class EmployeeData : INotifyPropertyChanged
    {
        private string _name;
        
        public string Name
        {
            get { return _name; }
            set { _name = value; OnPropertyChanged(); }
        }


        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;

        private void OnPropertyChanged([CallerMember] string ParameterName = "")
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(ParameterName));
            }
        }

        #endregion
    }
}

尝试使其工作

try to make it work

namespace AttributeTesting
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            this.Loaded += OnMainWindowLoaded;
        }

        void OnMainWindowLoaded(object sender, RoutedEventArgs e)
        {
            EmployeeData EmployeeData = new EmployeeData { Name = "GoldCoin" };

        }
    }
}

无法实现我的自定义属性。我该怎么做呢



注意：

我正在尝试实现.net 4.5具有的功能。我在.net 4.0中开发的解决方案中的相同：）

Unable to implement my custom attribute. what should i do next

Note:
I am trying to implement something that .net 4.5 has. The same in my solution which was developed in .net 4.0 :)

推荐答案

这称为属性。

这是MSDN页面关于CallerMemberNameAttribute：

CallerMemberNameAttribute [ ^ ]



您可以通过派生自属性类 [ ^ ]。

类名必须以属性字为后缀，但在使用时不会显示在你的代码中。

示例：

That is called an attribute.
Here is the MSDN page about the CallerMemberNameAttribute:
CallerMemberNameAttribute[^]

You can define your own attribute by deriving from Attribute Class[^].
The class name must be suffixed with 'Attribute' word, but this does not appear when you use it in your code.
Example:

public class MyOwnAttrAttribute : Attribute
{
   // ...
}

[MyOwnAttr]
public class MyDecoratedClass
{
   // ...
}

尝试将实现更改为：

public event PropertyChangedEventHandler PropertyChanged;

protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
    var handler = PropertyChanged;
    if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}

这篇关于CallerMemberName如何工作？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！