C# 图片加密解密的实例代码
jopen
10年前
using System; using System.Collections.Generic; using System.Text; using System.Security.Cryptography; using System.IO; namespace Net.Template.Common { /// <summary> /// 对图片的加密和解密 /// </summary> public class DEncrypt4ImageHelper { public DEncrypt4ImageHelper() { } #region 加密方法 图片加密 /// <summary> /// 图片加密 /// </summary> /// <param name="filePath">源文件</param> /// <param name="savePath">保存为文件名称</param> /// <param name="keyStr">密钥</param> public static void EncryptFile(string filePath, string savePath, string keyStr) { //通过des加密 DESCryptoServiceProvider des = new DESCryptoServiceProvider(); //通过流打开文件 FileStream fs = File.OpenRead(filePath); //获取文件二进制字符 byte[] inputByteArray = new byte[fs.Length]; //读流文件 fs.Read(inputByteArray, 0, (int)fs.Length); //关闭流 fs.Close(); //获得加密字符串二进制字符 byte[] keyByteArray = Encoding.Default.GetBytes(keyStr); //计算指定字节组指定区域哈希值 SHA1 ha = new SHA1Managed(); byte[] hb = ha.ComputeHash(keyByteArray); //加密密钥数组 byte[] sKey = new byte[8]; //加密变量 byte[] sIV = new byte[8]; for (int i = 0; i < 8; i++) sKey[i] = hb[i]; for (int i = 8; i < 16; i++) sIV[i - 8] = hb[i]; //获取加密密钥 des.Key = sKey; //设置加密初始化向量 des.IV = sIV; MemoryStream ms = new MemoryStream(); CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write); cs.Write(inputByteArray, 0, inputByteArray.Length); cs.FlushFinalBlock(); fs = File.OpenWrite(savePath); foreach (byte b in ms.ToArray()) { www.jbxue.com fs.WriteByte(b); } fs.Close(); cs.Close(); ms.Close(); } #endregion #region 解密方法 图片解密 /// <summary> /// 图片解密 /// </summary> /// <param name="filePath">源文件</param> /// <param name="savePath">保存文件</param> /// <param name="keyStr">密钥</param> public static void DecryptFile(string filePath, string savePath, string keyStr) { //通过des解密 DESCryptoServiceProvider des = new DESCryptoServiceProvider(); //通过流读取文件 FileStream fs = File.OpenRead(filePath); //获取文件二进制字符 byte[] inputByteArray = new byte[fs.Length]; //读取流文件 fs.Read(inputByteArray, 0, (int)fs.Length); //关闭流 fs.Close(); //密钥数组 byte[] keyByteArray = Encoding.Default.GetBytes(keyStr); //定义哈希变量 SHA1 ha = new SHA1Managed(); //计算指定字节组指定区域哈希值 byte[] hb = ha.ComputeHash(keyByteArray); //加密密钥数组 byte[] sKey = new byte[8]; //加密变量 byte[] sIV = new byte[8]; for (int i = 0; i < 8; i++) sKey[i] = hb[i]; for (int i = 8; i < 16; i++) sIV[i - 8] = hb[i]; //获取加密密钥 des.Key = sKey; //加密变量 des.IV = sIV; MemoryStream ms = new MemoryStream(); CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write); cs.Write(inputByteArray, 0, inputByteArray.Length); cs.FlushFinalBlock(); fs = File.OpenWrite(savePath); foreach (byte b in ms.ToArray()) { fs.WriteByte(b); } fs.Close(); cs.Close(); ms.Close(); } #endregion } }