如何根据名称获取属性值

Question

有没有办法根据对象的名称获取对象属性的值？

例如,如果我有:

public class Car : Vehicle
{
   public string Make { get; set; }
}

和

var car = new Car { Make="Ford" };

我想写一个方法,我可以传入属性名称,它将返回属性值.即:

public string GetPropertyValue(string propertyName)
{
   return the value of the property;
}

Answer 1

return car.GetType().GetProperty(propertyName).GetValue(car, null);

Answer 2

你必须使用反射

public object GetPropertyValue(object car, string propertyName)
{
   return car.GetType().GetProperties()
      .Single(pi => pi.Name == propertyName)
      .GetValue(car, null);
}

如果你想要真正的幻想,你可以使它成为一个扩展方法:

public static object GetPropertyValue(this object car, string propertyName)
{
   return car.GetType().GetProperties()
      .Single(pi => pi.Name == propertyName)
      .GetValue(car, null);
}

然后:

string makeValue = (string)car.GetPropertyValue("Make");

Answer 3

你想要反思

Type t = typeof(Car);
PropertyInfo prop = t.GetProperty("Make");
if(null != prop)
return prop.GetValue(this, null);

Answer 4

另外其他人回答，它很容易通过使用扩展方法获取任何对象的属性值，例如：

public static class Helper
    {
        public static object GetPropertyValue(this object T, string PropName)
        {
            return T.GetType().GetProperty(PropName) == null ? null : T.GetType().GetProperty(PropName).GetValue(T, null);
        }

    }

用法是：

Car foo = new Car();
var balbal = foo.GetPropertyValue("Make");

Answer 5

简单示例(客户端没有写反射硬代码)

class Customer
{
    public string CustomerName { get; set; }
    public string Address { get; set; }
    // approach here
    public string GetPropertyValue(string propertyName)
    {
        try
        {
            return this.GetType().GetProperty(propertyName).GetValue(this, null) as string;
        }
        catch { return null; }
    }
}
//use sample
static void Main(string[] args)
    {
        var customer = new Customer { CustomerName = "Harvey Triana", Address = "Something..." };
        Console.WriteLine(customer.GetPropertyValue("CustomerName"));
    }

Answer 6

扩展Adam Rackis的答案-我们可以像下面这样简单地使扩展方法通用：

public static TResult GetPropertyValue<TResult>(this object t, string propertyName)
{
    object val = t.GetType().GetProperties().Single(pi => pi.Name == propertyName).GetValue(t, null);
    return (TResult)val;
}

如果愿意，您也可以对此进行一些错误处理。