使用XML文件连接数据库并对密码进行加密解密的公共类

 一.xml:

 

<? xml version="1.0" encoding="gb2312" ?>
< constr >
   < checkstate > 1 </ checkstate >
   < server > data source=10.0.0.181; </ server >
   < database > initial catalog=jiang; </ database >
   < user > user id=sa; </ user >
   < pwd > FKeBrrB5/x8= </ pwd >
   < other > workstation id=10.0.0.181;pooling=true;packet size=4096;persist security info=False;timeout=600 </ other >
   < path > E:Jcs's work我的文件C#综合测试(datetime+form)WindowsApplication1inDebugWindowsApplication1.EXE </ path >
</ constr >

 

二.源代码与使用说明

使用说明:checkstate 是用来判断是否已经加过密的标志.

 

using  System;
using  System.Collections.Generic;
using  System.Text;
using  System.Security.Cryptography;
using  System.IO;
using  System.Windows.Forms;
using  System.Xml;

namespace  JcsExpLibary.加密公共类
... {
    public class Public_Use
    ...{
        public  static  string server ; //服务器
        public static string database ; //数据库
        public static string user  ;//用户名
        public static string pwd ; //密码

        "加密解密"#region "加密解密"

        public static string SetSecret(string filename)
        ...{
            if (!System.IO.File.Exists(filename))
            ...{
                MessageBox.Show("项目的配置文件被删除或移动，请联系开发人员！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                return "出错";
            }
            string returnvalue;
            int index;
            //密匙 
            byte[] b = ...{ 18, 68, 22, 238, 136, 21, 221, 65 };
            XmlDocument doc = new XmlDocument();
            doc.Load(filename);
            //根节点 
            XmlElement root = doc.DocumentElement;

            XmlNode servernode = root.SelectSingleNode("server");
            XmlNode databasenode = root.SelectSingleNode("database");
            XmlNode usernode = root.SelectSingleNode("user");
            XmlNode pwdnode = root.SelectSingleNode("pwd");
            XmlNode othernode = root.SelectSingleNode("other");
            XmlNode pathnode = root.SelectSingleNode("path");

            //检验是否已经加过密 
            XmlNode checklist = root.SelectSingleNode("checkstate");

            if (checklist.InnerText == "1")
            ...{
                //表示已经加密 
                //已经加密就直接解密 
                pwd = Decrypt(pwdnode.InnerText, b);
                index = pwd.IndexOf("=");
                if (index != -1)
                ...{
                    pwd = pwd.Substring(index + 1, pwd.Length - index - 2);
                }
            }
            else if (checklist.InnerText == "0")
            ...{
                //加密 
                pwd = pwdnode.InnerText;
                index = pwd.IndexOf("=");
                if (index != -1)
                ...{
                    pwd = pwd.Substring(index + 1, pwd.Length - index - 2);
                }
                pwdnode.InnerText = Encrypt(pwdnode.InnerText, b);
                checklist.InnerText = "1";
                //设置为已经加密完成 
                pathnode.InnerText = Application.ExecutablePath;
                StreamWriter sw = new StreamWriter(filename, false, Encoding.GetEncoding("gb2312"));
                XmlTextWriter xw = new XmlTextWriter(sw);
                //如何对输出进行格式设置 
                xw.Formatting = Formatting.Indented;
                //对元素内容进行缩进 
                doc.Save(xw);
                sw.Close();
            }
            //取得server 
            index = servernode.InnerText.IndexOf("=");
            if (index != -1)
            ...{
                server = servernode.InnerText.Substring(index + 1, servernode.InnerText.Length  - index - 2);
            }
            else
            ...{
                server = servernode.InnerText;
            }

            //取得database 
            index = databasenode.InnerText.IndexOf("=");
            if (index != -1)
            ...{
                database = databasenode.InnerText.Substring(index + 1, servernode.InnerText.Length - index - 2);
            }
            else
            ...{
                database = databasenode.InnerText;
            }
            //取得user 
            index = usernode.InnerText.IndexOf("=");
            if (index != -1)
            ...{
                user = usernode.InnerText.Substring(index + 1, usernode.InnerText.Length  - index - 2);
            }
            else
            ...{
                user = usernode.InnerText;
            }

            //----------------------------------------------- 
            returnvalue = servernode.InnerText + databasenode.InnerText + usernode.InnerText + "pwd=" + pwd + ";" + othernode.InnerText;
            return returnvalue;
        }
        //加密 
        public static string Encrypt(string datastr, byte[] key)
        ...{
            DESCryptoServiceProvider desc = new DESCryptoServiceProvider();

            byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(datastr);
            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms, desc.CreateEncryptor(key, key), CryptoStreamMode.Write);
            cs.Write(data, 0, data.Length);
            cs.FlushFinalBlock();

            return Convert.ToBase64String(ms.ToArray());
        }
        //解密 
        public static string Decrypt(string datastr, byte[] key)
        ...{
            string returnstr = null ;
            DESCryptoServiceProvider desc = new DESCryptoServiceProvider();

            byte[] data = Convert.FromBase64String(datastr);

            MemoryStream ms = new MemoryStream(data, 0, data.Length);

            CryptoStream cs = new CryptoStream(ms, desc.CreateDecryptor(key, key), CryptoStreamMode.Read);
            StreamReader sr = new StreamReader(cs);
            returnstr =  sr.ReadToEnd();
            return returnstr;
        }
        #endregion 
    }
}

 

 测试代码:

 

            _StrConstring  =  Public_Use.SetSecret(Application.StartupPath  +   " /appset.xml " );
            SqlConnection conn  =   new  SqlConnection(_StrConstring);
             try
             ... {
                conn.Open();
                SqlCommand cmd = new SqlCommand("select id,name,description from a_test",conn);
                SqlDataAdapter sqldpr = new SqlDataAdapter(cmd);
                DataTable tbl = new DataTable();
                sqldpr.Fill(tbl);
                this.dataGridView1.DataSource = tbl.DefaultView;
            }
             catch  (Exception ex)
             ... {
                MessageBox.Show(ex.ToString());
            }
             finally
             ... {
            }