c# winform 文件内容的加密解密

主要代码

加密:

#region 加密方法
public bool EncryptFile(string filePath,string savePath,string keyStr)
{
    DESCryptoServiceProvider des = new DESCryptoServiceProvider();
    if(keyStr=="")
        keyStr=key;
    FileStream fs=File.OpenRead(filePath);
    byte[] inputByteArray =new byte[fs.Length];
    fs.Read(inputByteArray,0,(int)fs.Length);
    fs.Close();
    byte[] keyByteArray=Encoding.Default.GetBytes(keyStr);
    SHA1 ha=new SHA1Managed();
    byte[] hb=ha.ComputeHash(keyByteArray);
    sKey=new byte[8];
    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];
    des.Key=sKey;
    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())
    {
        fs.WriteByte(b);
    }
    fs.Close();
    cs.Close();
    ms.Close();
    return true;
}
#endregion

解密:

#region 解密方法
public bool DecryptFile(string filePath,string savePath,string keyStr)
{
    DESCryptoServiceProvider des = new DESCryptoServiceProvider();
    if(keyStr=="")
        keyStr=key;
    FileStream fs=File.OpenRead(filePath);
    byte[] inputByteArray =new byte[fs.Length];
    fs.Read(inputByteArray,0,(int)fs.Length);
    fs.Close();
    byte[] keyByteArray=Encoding.Default.GetBytes(keyStr);
    SHA1 ha=new SHA1Managed();
    byte[] hb=ha.ComputeHash(keyByteArray);
    sKey=new byte[8];
    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];
    des.Key=sKey;
    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();
    return true;
}
#endregion