使用反射和Attribute动态显示代码中的注释内容
反射和Attribute是.NET的两种技术,可以应用在很多的地方。
反射可以反射类中的属性,方法,实现动态调用,也经常在三层工厂中使用,反射接口的实现。
Attribute,个人理解,就是一个特性,可以添加在任何自定义类型上面,然后添加一些注释,也是很有用的。
本篇就示例讲解一个他们的结合使用:使用反射和Attribute动态显示代码中的注释内容。其中也杂合它一些其他的内容,一个是前几天写的一个C#的加密解密算法,包括Silverlight的MD5算法。还有就是一个商品规格的计算方法,比如给出需要购买的总量,然后计算每种规格需要购买的数量,和总的花费。
结果如下图
代码如下
代码
<!--<br/ /><br/ />Code highlighting produced by Actipro CodeHighlighter (freeware)<br/ />http://www.CodeHighlighter.com/<br/ /><br/ />-->using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Security;
using System.Reflection;
namespace ConsoleApplication1
{
[AttributeUsage(AttributeTargets.Class)]
class CodeReviewAttribute : System.Attribute
{
private string _reviewer;
public string Reviewer
{
get { return _reviewer; }
}
private string _date;
public string Date
{
get { return _date; }
}
private string _comment;
public string Comment
{
get { return _comment; }
set { _comment = value; }
}
public CodeReviewAttribute(string reviewer, string date)
{
this._reviewer = reviewer;
this._date = date;
}
}
[CodeReview("swb", "2009-9-9", Comment = "代码不好")]
class MyClass
{
}
[AttributeUsage(AttributeTargets.Enum | AttributeTargets.Field)]
class NoteAttribute : System.Attribute
{
private string _name;
public string Name
{
get { return _name; }
}
public NoteAttribute(string name)
{
this._name = name;
}
}
enum Log
{
[Note("添加 用户")]
AddUser,
[Note("修改 用户")]
ModifyUser
}
class EnumDescription
{
public static string Parse(Log type)
{
FieldInfo fields = type.GetType().GetField(type.ToString());
object[] objs = fields.GetCustomAttributes(true);
return ((NoteAttribute)objs[0]).Name;
}
}
public interface IChinese
{
string Speak();
}
public class CNSpeaker : IChinese
{
#region Chinese Members
public string Speak()
{
return "Chinese";
}
#endregion
}
public interface IEnglish
{
string Speak();
}
public class ENSpeaker : IEnglish
{
#region English Members
string IEnglish.Speak()
{
return "English";
}
#endregion
}
class Program
{
static void Main(string[] args)
{
CNSpeaker cn = new CNSpeaker();
Console.WriteLine(cn.Speak());
IEnglish en = new ENSpeaker();
Console.WriteLine(en.Speak());
Console.WriteLine("---------------------");
string str = "123";
Console.WriteLine(string.Format("123 encrypt result: {0}", WebMD5Provider.WebFormMD5Encrypt(str)));
Console.WriteLine("---------------------");
MD5CryptoServiceProvider md5Provider = new MD5CryptoServiceProvider();
byte[] encryptedBytes = md5Provider.ComputeHash(Encoding.UTF8.GetBytes(str));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
Console.WriteLine(string.Format("123 encrypt result: {0}", sb.ToString()));
Console.WriteLine("---------------------");
System.Reflection.MemberInfo info = typeof(MyClass);
CodeReviewAttribute att = (CodeReviewAttribute)Attribute.GetCustomAttribute(info, typeof(CodeReviewAttribute));
if (att != null)
{
Console.WriteLine("MyClass 代码监察人:{0}", att.Reviewer);
Console.WriteLine("MyClass 检查时间:{0}", att.Date);
Console.WriteLine("MyClass 备注:{0}", att.Comment);
}
Console.WriteLine("---------------------");
Log log = Log.AddUser;
Console.WriteLine(string.Format ("Enum Log 的 AddUser 的注释是: {0}",EnumDescription.Parse(log)));
Console.WriteLine("---------------------");
Int64? bbb = 0;
int? aaa = 0;
Console.WriteLine("---------------------");
decimal area = 110;
Console.WriteLine("你的土地面积是:{0}", area);
decimal amount = 10m;
Console.WriteLine("你的每亩用量是是:{0}", amount );
decimal budget = 0;
List<pkgspec> pkgs = new List<pkgspec>();
pkgs.Add(new pkgspec() { amount = 200, price = 180, id = 2 });
pkgs.Add(new pkgspec() { amount = 100, price = 100, id = 1 });
pkgs.Add(new pkgspec() { amount = 250, price = 250, id = 3 });
pkgs.Sort(new Comparison<pkgspec>(compareDesc));
// pkgs.Sort(new Comparison<pkgspec>(compareAsc));
decimal totalAmount = area * amount;
Console.WriteLine("你的总共用量是:{0}", totalAmount);
int num = 0;
List<pkgselect> select = new List<pkgselect>();
foreach (pkgspec pkg in pkgs)
{
if (totalAmount % pkg.amount == totalAmount)
{
num =1;
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = num, price=pkg.price });
break;
}
else if (totalAmount % pkg.amount == 0)
{
num = (int)(totalAmount / pkg.amount);
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = (int)(totalAmount / pkg.amount) , price=pkg.price });
break;
}
else
{
num = (int)(totalAmount / pkg.amount);
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = num , price=pkg.price });
totalAmount = totalAmount - num * pkg.amount;
continue;
}
}
foreach (pkgselect s in select)
{
Console.WriteLine("你需要购买的包装编号是:{0}, 数量是 {1} 个 , 单价是 {2}", s.id, s.num, s.price);
}
Console.WriteLine("你购买的总价是: {0}", budget);
Console.ReadLine();
}
private static int compareAsc(pkgspec pkg1, pkgspec pkg2)
{
if (pkg1.amount > pkg2.amount)
return 1;
if (pkg1.amount < pkg2.amount)
return -1;
else
return 0;
}
private static int compareDesc(pkgspec pkg1, pkgspec pkg2)
{
if (pkg1.amount < pkg2.amount)
return 1;
if (pkg1.amount > pkg2.amount)
return -1;
else
return 0;
}
}
/// <summary>
/// 选中的包装
/// </summary>
class pkgselect
{
/// <summary>
/// 选中ID
/// </summary>
public int id;
/// <summary>
/// 购买数量
/// </summary>
public int num;
/// <summary>
/// 单价
/// </summary>
public decimal price;
}
/// <summary>
/// 包装类型
/// </summary>
class pkgspec : IComparable<pkgspec>
{
/// <summary>
/// 编号
/// </summary>
public int id;
/// <summary>
/// 包装量
/// </summary>
public decimal amount;
/// <summary>
/// 价格
/// </summary>
public decimal price;
#region IComparable<pkgspec> Members
public int CompareTo(pkgspec other)
{
if (this.amount > other.amount)
return 1;
if (this.amount == other.amount)
return 0;
else
return -1;
}
#endregion
}
}
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Security;
using System.Reflection;
namespace ConsoleApplication1
{
[AttributeUsage(AttributeTargets.Class)]
class CodeReviewAttribute : System.Attribute
{
private string _reviewer;
public string Reviewer
{
get { return _reviewer; }
}
private string _date;
public string Date
{
get { return _date; }
}
private string _comment;
public string Comment
{
get { return _comment; }
set { _comment = value; }
}
public CodeReviewAttribute(string reviewer, string date)
{
this._reviewer = reviewer;
this._date = date;
}
}
[CodeReview("swb", "2009-9-9", Comment = "代码不好")]
class MyClass
{
}
[AttributeUsage(AttributeTargets.Enum | AttributeTargets.Field)]
class NoteAttribute : System.Attribute
{
private string _name;
public string Name
{
get { return _name; }
}
public NoteAttribute(string name)
{
this._name = name;
}
}
enum Log
{
[Note("添加 用户")]
AddUser,
[Note("修改 用户")]
ModifyUser
}
class EnumDescription
{
public static string Parse(Log type)
{
FieldInfo fields = type.GetType().GetField(type.ToString());
object[] objs = fields.GetCustomAttributes(true);
return ((NoteAttribute)objs[0]).Name;
}
}
public interface IChinese
{
string Speak();
}
public class CNSpeaker : IChinese
{
#region Chinese Members
public string Speak()
{
return "Chinese";
}
#endregion
}
public interface IEnglish
{
string Speak();
}
public class ENSpeaker : IEnglish
{
#region English Members
string IEnglish.Speak()
{
return "English";
}
#endregion
}
class Program
{
static void Main(string[] args)
{
CNSpeaker cn = new CNSpeaker();
Console.WriteLine(cn.Speak());
IEnglish en = new ENSpeaker();
Console.WriteLine(en.Speak());
Console.WriteLine("---------------------");
string str = "123";
Console.WriteLine(string.Format("123 encrypt result: {0}", WebMD5Provider.WebFormMD5Encrypt(str)));
Console.WriteLine("---------------------");
MD5CryptoServiceProvider md5Provider = new MD5CryptoServiceProvider();
byte[] encryptedBytes = md5Provider.ComputeHash(Encoding.UTF8.GetBytes(str));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
Console.WriteLine(string.Format("123 encrypt result: {0}", sb.ToString()));
Console.WriteLine("---------------------");
System.Reflection.MemberInfo info = typeof(MyClass);
CodeReviewAttribute att = (CodeReviewAttribute)Attribute.GetCustomAttribute(info, typeof(CodeReviewAttribute));
if (att != null)
{
Console.WriteLine("MyClass 代码监察人:{0}", att.Reviewer);
Console.WriteLine("MyClass 检查时间:{0}", att.Date);
Console.WriteLine("MyClass 备注:{0}", att.Comment);
}
Console.WriteLine("---------------------");
Log log = Log.AddUser;
Console.WriteLine(string.Format ("Enum Log 的 AddUser 的注释是: {0}",EnumDescription.Parse(log)));
Console.WriteLine("---------------------");
Int64? bbb = 0;
int? aaa = 0;
Console.WriteLine("---------------------");
decimal area = 110;
Console.WriteLine("你的土地面积是:{0}", area);
decimal amount = 10m;
Console.WriteLine("你的每亩用量是是:{0}", amount );
decimal budget = 0;
List<pkgspec> pkgs = new List<pkgspec>();
pkgs.Add(new pkgspec() { amount = 200, price = 180, id = 2 });
pkgs.Add(new pkgspec() { amount = 100, price = 100, id = 1 });
pkgs.Add(new pkgspec() { amount = 250, price = 250, id = 3 });
pkgs.Sort(new Comparison<pkgspec>(compareDesc));
// pkgs.Sort(new Comparison<pkgspec>(compareAsc));
decimal totalAmount = area * amount;
Console.WriteLine("你的总共用量是:{0}", totalAmount);
int num = 0;
List<pkgselect> select = new List<pkgselect>();
foreach (pkgspec pkg in pkgs)
{
if (totalAmount % pkg.amount == totalAmount)
{
num =1;
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = num, price=pkg.price });
break;
}
else if (totalAmount % pkg.amount == 0)
{
num = (int)(totalAmount / pkg.amount);
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = (int)(totalAmount / pkg.amount) , price=pkg.price });
break;
}
else
{
num = (int)(totalAmount / pkg.amount);
budget += num * pkg.price;
select.Add(new pkgselect() { id = pkg.id, num = num , price=pkg.price });
totalAmount = totalAmount - num * pkg.amount;
continue;
}
}
foreach (pkgselect s in select)
{
Console.WriteLine("你需要购买的包装编号是:{0}, 数量是 {1} 个 , 单价是 {2}", s.id, s.num, s.price);
}
Console.WriteLine("你购买的总价是: {0}", budget);
Console.ReadLine();
}
private static int compareAsc(pkgspec pkg1, pkgspec pkg2)
{
if (pkg1.amount > pkg2.amount)
return 1;
if (pkg1.amount < pkg2.amount)
return -1;
else
return 0;
}
private static int compareDesc(pkgspec pkg1, pkgspec pkg2)
{
if (pkg1.amount < pkg2.amount)
return 1;
if (pkg1.amount > pkg2.amount)
return -1;
else
return 0;
}
}
/// <summary>
/// 选中的包装
/// </summary>
class pkgselect
{
/// <summary>
/// 选中ID
/// </summary>
public int id;
/// <summary>
/// 购买数量
/// </summary>
public int num;
/// <summary>
/// 单价
/// </summary>
public decimal price;
}
/// <summary>
/// 包装类型
/// </summary>
class pkgspec : IComparable<pkgspec>
{
/// <summary>
/// 编号
/// </summary>
public int id;
/// <summary>
/// 包装量
/// </summary>
public decimal amount;
/// <summary>
/// 价格
/// </summary>
public decimal price;
#region IComparable<pkgspec> Members
public int CompareTo(pkgspec other)
{
if (this.amount > other.amount)
return 1;
if (this.amount == other.amount)
return 0;
else
return -1;
}
#endregion
}
}
代码
<!--<br/ /><br/ />Code highlighting produced by Actipro CodeHighlighter (freeware)<br/ />http://www.CodeHighlighter.com/<br/ /><br/ />-->using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Security;
using System.Security.Cryptography;
using System.IO;
namespace ConsoleApplication1
{
/// <summary>
/// 字符串加解密工具类
/// </summary>
public static class EncryptUtility
{
#region WinForm 的MD5和SHA1哈希,使得和System.Web.Security.FormsAuthentication的结果一致
public static string WinFormMD5Encrypt(string data)
{
MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
byte[] encryptedBytes = md5.ComputeHash(Encoding.ASCII.GetBytes(data));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
return sb.ToString().ToUpper();
}
public static string WinFormSHA1Encrypt(string data)
{
SHA1CryptoServiceProvider md5 = new SHA1CryptoServiceProvider();
byte[] encryptedBytes = md5.ComputeHash(Encoding.ASCII.GetBytes(data));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
return sb.ToString().ToUpper();
}
#endregion
#region WebForm中的 MD5 和 SHA1 哈希
/// <summary>
/// 返回MD5哈希结果
/// </summary>
/// <param name="password"></param>
/// <returns></returns>
public static string WebFormMD5Encrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
return FormsAuthentication.HashPasswordForStoringInConfigFile(data, "md5");
}
/// <summary>
/// 返回SHA1哈希结果
/// </summary>
/// <param name="password"></param>
/// <returns></returns>
public static string WebFormSHA1Encrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
return FormsAuthentication.HashPasswordForStoringInConfigFile(data, "sha1");
}
#endregion
#region 普通的字符变换加解密
/// <summary>
/// 普通字符还变
/// 加密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string CommonEncrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
string result = string.Empty;
int len = data.Length;
for (int i = 0; i < len; i++)
{
result += (char)(data[i] + 10 - 1 * 2);
}
return result;
}
/// <summary>
/// 普通的字符变换
/// 解密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string CommonDecrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
string result = string.Empty;
int len = data.Length;
for (int i = 0; i < len; i++)
{
result += (char)(data[i] - 10 + 1 * 2);
}
return result;
}
#endregion
#region 带有**的加解密
private static readonly string KEY_64 = System.Configuration.ConfigurationManager.AppSettings["key_64"];
/// <summary>
/// 带有**的加解密
/// 加密
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static string KeyEncrypt(string data)
{
using (DESCryptoServiceProvider provider = new DESCryptoServiceProvider())
{
byte[] inputByteArray = Encoding.UTF8.GetBytes(data);
provider.Key = ASCIIEncoding.ASCII.GetBytes(KEY_64.Substring(0, 8));
provider.IV = ASCIIEncoding.ASCII.GetBytes(KEY_64);
MemoryStream ms = new MemoryStream();
using (CryptoStream cs = new CryptoStream(ms, provider.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
cs.Close();
}
string str = Convert.ToBase64String(ms.ToArray());
ms.Close();
return str;
}
}
/// <summary>
/// 带有**的加解密
/// 解密
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static string KeyDecrypt(string data)
{
byte[] inputByteArray = Convert.FromBase64String(data);
using (DESCryptoServiceProvider provider = new DESCryptoServiceProvider())
{
provider.Key = ASCIIEncoding.ASCII.GetBytes(KEY_64.Substring(0, 8));
provider.IV = ASCIIEncoding.ASCII.GetBytes(KEY_64);
MemoryStream ms = new MemoryStream();
using (CryptoStream cs = new CryptoStream(ms, provider.CreateDecryptor(), CryptoStreamMode.Write))
{
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
cs.Close();
}
string str = Encoding.UTF8.GetString(ms.ToArray());
ms.Close();
return str;
}
}
#endregion
}
public class
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Security;
using System.Security.Cryptography;
using System.IO;
namespace ConsoleApplication1
{
/// <summary>
/// 字符串加解密工具类
/// </summary>
public static class EncryptUtility
{
#region WinForm 的MD5和SHA1哈希,使得和System.Web.Security.FormsAuthentication的结果一致
public static string WinFormMD5Encrypt(string data)
{
MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
byte[] encryptedBytes = md5.ComputeHash(Encoding.ASCII.GetBytes(data));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
return sb.ToString().ToUpper();
}
public static string WinFormSHA1Encrypt(string data)
{
SHA1CryptoServiceProvider md5 = new SHA1CryptoServiceProvider();
byte[] encryptedBytes = md5.ComputeHash(Encoding.ASCII.GetBytes(data));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < encryptedBytes.Length; i++)
{
sb.AppendFormat("{0:x2}", encryptedBytes[i]);
}
return sb.ToString().ToUpper();
}
#endregion
#region WebForm中的 MD5 和 SHA1 哈希
/// <summary>
/// 返回MD5哈希结果
/// </summary>
/// <param name="password"></param>
/// <returns></returns>
public static string WebFormMD5Encrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
return FormsAuthentication.HashPasswordForStoringInConfigFile(data, "md5");
}
/// <summary>
/// 返回SHA1哈希结果
/// </summary>
/// <param name="password"></param>
/// <returns></returns>
public static string WebFormSHA1Encrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
return FormsAuthentication.HashPasswordForStoringInConfigFile(data, "sha1");
}
#endregion
#region 普通的字符变换加解密
/// <summary>
/// 普通字符还变
/// 加密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string CommonEncrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
string result = string.Empty;
int len = data.Length;
for (int i = 0; i < len; i++)
{
result += (char)(data[i] + 10 - 1 * 2);
}
return result;
}
/// <summary>
/// 普通的字符变换
/// 解密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string CommonDecrypt(string data)
{
if (string.IsNullOrEmpty(data))
throw new Exception("加密字符串不能为空");
string result = string.Empty;
int len = data.Length;
for (int i = 0; i < len; i++)
{
result += (char)(data[i] - 10 + 1 * 2);
}
return result;
}
#endregion
#region 带有**的加解密
private static readonly string KEY_64 = System.Configuration.ConfigurationManager.AppSettings["key_64"];
/// <summary>
/// 带有**的加解密
/// 加密
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static string KeyEncrypt(string data)
{
using (DESCryptoServiceProvider provider = new DESCryptoServiceProvider())
{
byte[] inputByteArray = Encoding.UTF8.GetBytes(data);
provider.Key = ASCIIEncoding.ASCII.GetBytes(KEY_64.Substring(0, 8));
provider.IV = ASCIIEncoding.ASCII.GetBytes(KEY_64);
MemoryStream ms = new MemoryStream();
using (CryptoStream cs = new CryptoStream(ms, provider.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
cs.Close();
}
string str = Convert.ToBase64String(ms.ToArray());
ms.Close();
return str;
}
}
/// <summary>
/// 带有**的加解密
/// 解密
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static string KeyDecrypt(string data)
{
byte[] inputByteArray = Convert.FromBase64String(data);
using (DESCryptoServiceProvider provider = new DESCryptoServiceProvider())
{
provider.Key = ASCIIEncoding.ASCII.GetBytes(KEY_64.Substring(0, 8));
provider.IV = ASCIIEncoding.ASCII.GetBytes(KEY_64);
MemoryStream ms = new MemoryStream();
using (CryptoStream cs = new CryptoStream(ms, provider.CreateDecryptor(), CryptoStreamMode.Write))
{
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
cs.Close();
}
string str = Encoding.UTF8.GetString(ms.ToArray());
ms.Close();
return str;
}
}
#endregion
}
public class