C#中怎样访问private?
C#中怎样访问private修饰的东西? --------------------编程问答-------------------- 反射 --------------------编程问答-------------------- private 关键字是一个成员访问修饰符。私有访问是允许的最低访问级别。私有成员只有在声明它们的类和结构体中才是可访问的 --------------------编程问答-------------------- 怎样用反射呢？？？ --------------------编程问答-------------------- private成员只允许内部访问要外部使用请使用public修饰符 --------------------编程问答-------------------- private 就是不让在外部访问，你为什么要访问，要让能访问到，为什么不用public呢 --------------------编程问答-------------------- 都private了还访问什么？ 这不反着干吗？
为private的字段加公开属性吧 --------------------编程问答-------------------- 一般是写一个public 的函数来操作private的变量 --------------------编程问答--------------------
//-------------------------------------------------------------------------------------------编程问答-------------------- privat-私有变量! --------------------编程问答--------------------
// This file is part of the Microsoft .NET Framework SDK Code Samples.
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//This source code is intended only as a supplement to Microsoft
//Development Tools and/or on-line documentation. See these other
//materials for detailed information regarding Microsoft code samples.
//
//THIS CODE AND INFORMATION ARE PROVIDED AS IS WITHOUT WARRANTY OF ANY
//KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
//IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
//PARTICULAR PURPOSE.
//
/*=====================================================================
File: Invoke.cs
Summary: Demonstrates how to use reflection invoke.
Warning: This sample shows how to invoke ANY method via reflection on ANY location.
This can potentially be a security issue.
When implementing this pattern in your code be sure to take appropriate security measures,
such as hosting inside an AppDomain with locked down security permission.
=====================================================================*/
using System;
using System.Globalization;
using System.Text;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
using System.IO;
namespace Microsoft.Samples
{
public sealed class App
{
private App()
{
}
public static void Main(String[] args)
{
if (args.Length < 3)
{
Usage();
return;
}
Assembly assembly;
Type type;
try
{
// Load the requested assembly and get the requested type
assembly = Assembly.LoadFrom(args[0]);
type = assembly.GetType(args[1], true);
}
catch (FileNotFoundException)
{
Console.WriteLine("Could not load Assembly: \"{0}\"", args[0]);
return;
}
catch (TypeLoadException)
{
Console.WriteLine("Could not load Type: \"{0}\"\nfrom assembly: \"{1}\"", args[1], args[0]);
return;
}
// Get the methods from the type
MethodInfo[] methods = type.GetMethods();
if (methods == null)
{
Console.WriteLine("No Matching Types Found");
return;
}
// Make a new array that holds only the args for the call
String[] newArgs = new String[args.Length - 3];
if (newArgs.Length != 0)
{
Array.Copy(args, 3, newArgs, 0, newArgs.Length);
}
// Try each method for a match
StringBuilder failureExcuses = new StringBuilder();
foreach (MethodInfo m in methods)
{
Object obj = null;
try
{
obj = AttemptMethod(type, m, args[2], newArgs);
}
catch (CustomException e)
{
failureExcuses.Append(e.Message + "\n");
continue;
}
// If we make it this far without a throw, our job is done!
Console.WriteLine(obj);
return;
}
Console.WriteLine("Suitable method not found!");
Console.WriteLine("Here are the reasons:\n" + failureExcuses);
}
// Checks a method for a signature match, and invokes it if there is one
private static Object AttemptMethod(Type type, MethodInfo method, String name, String[] args)
{
// Name does not match?
if (String.Compare(method.Name, name, false, CultureInfo.InvariantCulture) != 0)
{
throw new CustomException(method.DeclaringType + "." + method.Name + ": Method Name Doesn't Match!");
}
// Wrong number of parameters?
ParameterInfo[] param = method.GetParameters();
if (param.Length != args.Length)
{
throw new CustomException(method.DeclaringType + "." + method.Name + ": Method Signatures Don't Match!");
}
// Ok, can we convert the strings to the right types?
Object[] newArgs = new Object[args.Length];
for (int index = 0; index < args.Length; index++)
{
try
{
newArgs[index] = Convert.ChangeType(args[index], param[index].ParameterType, CultureInfo.InvariantCulture);
}
catch (Exception e)
{
throw new CustomException(method.DeclaringType + "." + method.Name + ": Argument Conversion Failed", e);
}
}
// We made it this far, lets see if we need an instance of this type
Object instance = null;
if (!method.IsStatic)
{
instance = Activator.CreateInstance(type);
}
// ok, let's invoke this one!
return method.Invoke(instance, newArgs);
}
// Print usage
private static void Usage()
{
Console.WriteLine("Usage:\n" + " Invoke [Assembly] [Type] [Method] [Parameters...]");
}
class CustomException : Exception
{
public CustomException(String m):base(m) { }
public CustomException(String m, Exception n):base(m,n) { }
}
}
}
--------------------编程问答-------------------- 不是上面大哥说的哪个效果！So Sorry!你那是字段 谢谢！ --------------------编程问答-------------------- public的外部才可以访问 --------------------编程问答-------------------- private可以用反射访问 --------------------编程问答-------------------- System.Reflection.Assembly asm = System.Reflection.Assembly.Load(namespace);
//楼主要这种效果？
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
asm.GetType().GetMethods()//获取public方法
asm.GetType().FindMembers(MemberTypes.Method, BindingFlags.Default|BindingFlags.NonPublic | BindingFlags.Instance , null, null);
//注意FindMembers的第二个参数,是Flag,他们必须与 Public 或 NonPublic 一起指定 Instance 或 Static，否则将不返回成员。
估计应该可以成的吧
--------------------编程问答--------------------
Assembly ass = Assembly.Load("ConsoleApplication");
object structInstance = ass.CreateInstance("ConsoleApplication.PrivateField");
Type structType = structInstance.GetType();
BindingFlags bf = BindingFlags.Instance | BindingFlags.NonPublic;
FieldInfo fi = structType.GetField("ID",bf);
Console.WriteLine("ID oldValue:{0}", fi.GetValue(structInstance));
fi.SetValue(structInstance, 1);
Console.WriteLine("ID newValue:{0}", fi.GetValue(structInstance));
fi = structType.GetField("Name", bf);
Console.WriteLine("Name oldValue:{0}", fi.GetValue(structInstance));
fi.SetValue(structInstance, "Sandy");
Console.WriteLine("Name newValue:{0}", fi.GetValue(structInstance));
--------------------编程问答-------------------- 要是 设了private 又先在外部访问，那干脆 就public 吧， --------------------编程问答-------------------- 包装get/set对 --------------------编程问答-------------------- 我想请教一下，访问private达到什么目的 --------------------编程问答-------------------- 不明白
namespace ConsoleApplication
{
class PrivateField
{
private int ID = 0;
private string Name = "";
}
}
--------------------编程问答-------------------- 反射
属性，[成员]方法， --------------------编程问答-------------------- private僅類內部成員變量及成員函數訪問
--------------------编程问答-------------------- 反射可以。
楼主既然问，那必然是迫不得已得这样用了。我也遇到过这样的问题。实际情况是千变万化的。CSDN上真是，搜索到个问题的解决方法，一看是CSDN的，都不想来看。很少有人在回答，一堆人在废话。还给你解释一下private是私有的，谁TM不知道啊 --------------------编程问答-------------------- 类内部做一个接口间接访问不行吗 --------------------编程问答-------------------- 搞不懂，楼主什么意思。 --------------------编程问答-------------------- 封装.. --------------------编程问答-------------------- 封装处理
除非是研究反射知识。 --------------------编程问答-------------------- 一般是 声明一个字段是private的
private string _str;
然后提供一个public 的方法，来修改字段。比如
public void SetStr(string str)
{
_str = str;
}
这样实现了隐藏了字段。但提供了修改这个字段的效果。 --------------------编程问答-------------------- 如果说的是方法
可以写个类来继承
继承的类就拥有了这个私有方法
在继承的类写个公共方法，利用反射来调用这个私有方法 --------------------编程问答-------------------- 用属性把！ --------------------编程问答-------------------- 属性访问啊 --------------------编程问答-------------------- 如果要访问为什么要用private？public就好
补充：.NET技术 , C#
