Question

因此，PropertyInfo有一个GetSetMethod方法，该方法返回此属性的setter方法。它还有一个相同的SetMethod属性（据我所知）。

我问这个是因为看起来GetSetMethod如果属性不公开则返回null，而SetMethod仍然有效。

我在MSDN上找不到多少。

Answer 1

他们做同样的事情，但属性是新增加的：已经在.NET 4.5中添加了，而GetSetMethod自.NET 2.0以来一直存在。

唯一的区别是属性将返回setter，即使它是非公共的，而该方法只返回public个。来自文档：

返回此属性的 public set访问器。 [Method documentation]

VS

获取此属性的set访问器。 [Property documentation]

Answer 2

你是对的。

那是来自mscorlib（刚刚使用过dotPeek）：

    /// <summary>
    /// Returns the public set accessor for this property.
    /// </summary>
    /// 
    /// <returns>
    /// The MethodInfo object representing the Set method for this property if the set accessor is public, or null if the set accessor is not public.
    /// </returns>
    [__DynamicallyInvokable]
    [TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")]
    public MethodInfo GetSetMethod()
    {
      return this.GetSetMethod(false);
    }

    /// <summary>
    /// When overridden in a derived class, returns the set accessor for this property.
    /// </summary>
    /// 
    /// <returns>
    /// Value Condition A <see cref="T:System.Reflection.MethodInfo"/> object representing the Set method for this property. The set accessor is public.-or- <paramref name="nonPublic"/> is true and the set accessor is non-public. null<paramref name="nonPublic"/> is true, but the property is read-only.-or- <paramref name="nonPublic"/> is false and the set accessor is non-public.-or- There is no set accessor.
    /// </returns>
    /// <param name="nonPublic">Indicates whether the accessor should be returned if it is non-public. true if a non-public accessor is to be returned; otherwise, false. </param><exception cref="T:System.Security.SecurityException">The requested method is non-public and the caller does not have <see cref="T:System.Security.Permissions.ReflectionPermission"/> to reflect on this non-public method. </exception>
    [__DynamicallyInvokable]
    public abstract MethodInfo GetSetMethod(bool nonPublic);

    [__DynamicallyInvokable]
    public virtual MethodInfo SetMethod
    {
      [__DynamicallyInvokable, TargetedPatchingOptOut("Performance critical to inline this type of method across NGen image boundaries")] get
      {
        return this.GetSetMethod(true);
      }
    }

Answer 3

SetMethod只是GetSetMethod(true)的快捷方式（即无论是否公开，它都会返回setter方法）。它以这种方式实现：

public virtual MethodInfo SetMethod
{   
    get
    {
        return this.GetSetMethod(true);
    }
}

PropertyInfo上的GetSetMethod和SetMethod有什么区别？

3 个答案: