如何通过lambda表达式传递属性？

Question

我的项目中有一些单元测试，我们希望能够设置一些具有私人设置器的属性。

public static void SetPrivateProperty(this object sourceObject, string propertyName, object propertyValue) 
{ 
    sourceObject.GetType().GetProperty(propertyName).SetValue(sourceObject, propertyValue, null); 
} 

假设我有一个像这样的的TestObject：

public class TestObject 
{ 
    public int TestProperty{ get; private set; } 
} 

然后我可以在我的单元测试调用此如下：目前我通过反射和这个扩展方法做

myTestObject.SetPrivateProperty("TestProperty", 1); 

但是，我想在编译时验证属性名称，因此我希望能够通过通过表达式的属性，如下所示：

myTestObject.SetPrivateProperty(o => o.TestProperty, 1); 

我该怎么做？

Answer 1

新的C＃6.0：nameof（财产）

Answer 2

如果吸气剂是公共的，那么以下应该起作用。它会给你一个看起来像这样的扩展方法：

var propertyName = myTestObject.NameOf(o => o.TestProperty); 

它需要一个公共的getter。我希望在某种程度上，像这样的反射功能可以融入语言中。

public static class Name 
{ 
    public static string Of(LambdaExpression selector) 
    { 
     if (selector == null) throw new ArgumentNullException("selector"); 

     var mexp = selector.Body as MemberExpression; 
     if (mexp == null) 
     { 
      var uexp = (selector.Body as UnaryExpression); 
      if (uexp == null) 
       throw new TargetException(
        "Cannot determine the name of a member using an expression because the expression provided cannot be converted to a '" + 
        typeof(UnaryExpression).Name + "'." 
       ); 
      mexp = uexp.Operand as MemberExpression; 
     } 

     if (mexp == null) throw new TargetException(
      "Cannot determine the name of a member using an expression because the expression provided cannot be converted to a '" + 
      typeof(MemberExpression).Name + "'." 
     ); 
     return mexp.Member.Name; 
    } 

    public static string Of<TSource>(Expression<Func<TSource, object>> selector) 
    { 
     return Of<TSource, object>(selector); 
    } 

    public static string Of<TSource, TResult>(Expression<Func<TSource, TResult>> selector) 
    { 
     return Of(selector as LambdaExpression); 
    } 
} 

public static class NameExtensions 
{ 
    public static string NameOf<TSource, TResult>(this TSource obj, Expression<Func<TSource, TResult>> selector) 
    { 
     return Name.Of(selector); 
    } 
}