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  • 利用Lambda获取属性名称

    感谢下面这篇博文给我的思路:

    http://www.cnblogs.com/daimage/archive/2012/04/10/2440186.html

    上面文章的博主给出的代码是可用的,但是调用方法时需要写的代码过于冗长,例如博主给出的示例代码

    var name = TypeInfoHelper.GetClassPropertiesName<MyClass,List<string>>(s => myClass.UserName);

    代码中的List<string>为MyClass.UserName属性的类型,如果要获取一个类型为int的Flag属性还得相应的改为下面这个样子

    var name = TypeInfoHelper.GetClassPropertiesName<MyClass,int>(s => customer.Flag);

    我想把其中的传入泛型参数的代码拿掉,变成这样子:

    TypeInfoHelper.GetPropertyName(s=>myClass.UserName)

    是不是变得非常简洁?下面即是全部代码,再次感谢代码哥,致敬!

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Linq.Expressions;
    using System.Text;
    
    namespace ConsoleApplication1
    {
        class Program
        {
            static void Main(string[] args)
            {
                var cust = new Customer();
                var addr = new Address(cust);
                string name1 = TypeInfoHelper.GetPropertyName(p => cust.Flag);
                Console.WriteLine(name1);
                string name2 = TypeInfoHelper.GetPropertyName(p => addr.Owner.Remark);
                Console.WriteLine(name2);
                string name3 = TypeInfoHelper.GetPropertyName(p => cust.Orders);
                Console.WriteLine(name3);
                string name4 = TypeInfoHelper.GetPropertyName(p => cust.Orders.FirstOrDefault().Price);
                Console.WriteLine(name4);
                Console.ReadLine();
            }
        }
    
        public class TypeInfoHelper
        {
            public static string GetPropertyName(Expression<Func<Object, Object>> propery)
            {
                var body = propery.Body.ToString();
                return body.Substring(body.LastIndexOf(".") + 1);
            }
    
        }
    
        public class Customer
        {
            public string Name { get; set; }
            public string Remark { get; set; }
            public int Flag { get; set; }
    
            public List<string> Contacts { get; set; }
            public List<Order> Orders { get; set; }
        }
    
        public class Order
        {
            public decimal Price { get; set; }
        }
    
        public class Address
        {
            private Customer customer;
    
            public string Country { get; set; }
            public string State { get; set; }
            public string Street { get; set; }
    
            public Customer Owner
            {
                get { return customer; }
            }
    
            public Address(Customer owner)
            {
                this.customer = owner;
            }
        }
    
    }
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  • 原文地址:https://www.cnblogs.com/wiseant/p/3949762.html
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