如何设置名称为字符串形式的对象的属性

Question

开发环境:Visual studio 2010, c#， . net 4.0, Winforms应用程序。在我开始看这个类之前:

public class Car
{
   private string _break;         
   public string Break
   {
      get { return _break; }
      set { _break = value; }
   }
}

我还有另一个类:

public class Runner
{
   Car cObj = new Car();
   string propertyName = "Break";
   //cobj.Break = "diskBreak"; I can do this but I have property name in string format  
   cobj[propertyName] = "diskBreak"; // I have the property name in string format
   // and I want to make it's Property format please suggest how to to this?
}

我有字符串格式的属性名我想在property中转换它并初始化它。请告诉我如何执行这个，我认为这是可能的使用反射。但是我不知道。

Answer 1

如果真的不需要类，可以使用反射或ExpandoObject。

// 1. Reflection
public void SetByReflection(){
    Car cObj = new Car();
    string propName = "Break";
    cObj.GetType().GetProperty(propName).SetValue(cObj, "diskBreak");
    Console.WriteLine (cObj.Break);
}
// 2. ExpandoObject
public void UseExpandoObject(){
    dynamic car = new ExpandoObject();
    string propName = "Break";
    ((IDictionary<string, object>)car)[propName] = "diskBreak";
    Console.WriteLine (car.Break);
}

一个有趣的选择是使用"静态"反射，如果你可以避免使用表达式而不是字符串——在你的情况下很可能是不必要的，但我认为我不妨对比一下不同的方法。

// 3. "Static" Reflection
public void UseStaticReflection(){
    Car car = new Car();
    car.SetProperty(c => c.Break, "diskBreak");
    Console.WriteLine (car.Break);
}
public static class PropExtensions{
    public static void SetProperty<T, TProp>(this T obj, Expression<Func<T, TProp>> propGetter, TProp value){       
        var propName = ((MemberExpression)propGetter.Body).Member.Name;
        obj.GetType().GetProperty(propName).SetValue(obj, value);
    } 
}

Answer 2

您可以使用Reflection来完成此操作，例如:

// create a Car object
Car cObj = new Car();
// get the type of car Object
var carType = typeof(cObj);
// get the propertyInfo object respective about the property you want to work
var property = carType.GetProperty("Break");
// set the value of the property in the object car
property.SetValue(cObj, "diskBreak");