XML encryption and decryption

Encryption and decryption of XML or TXT files

# Region encrypts and decrypts files
Static string IV = "password ";
Static string key = "password ";

/// <Summary>
/// DES encryption offset, which must be an> = 8-bit long string
/// </Summary>
Public static string IV
{
Get {return IV ;}
Set {IV = value ;}
}

///

// des-encrypted private key, it must be an 8-bit long string
//
Public static string key
{< br> get {return key ;}
set {key = value ;}< BR >}

/// <Summary>
/// Perform DES encryption on the file content
/// </Summary>
/// <Param name = "sourcefile"> absolute path of the file to be encrypted </param>
/// <Param name = "destfile"> absolute path of the encrypted file </param>
Public static void encryptfile (string sourcefile, string destfile)
{

If (! File. exists (sourcefile) throw new filenotfoundexception ("the specified file path does not exist! ", Sourcefile );

Byte [] btkey = encoding. Default. getbytes (key );
Byte [] btiv = encoding. Default. getbytes (IV );
Descryptoserviceprovider des = new descryptoserviceprovider ();
Byte [] btfile = file. readallbytes (sourcefile );


Using (filestream FS = new filestream (destfile, filemode. Create, fileaccess. Write ))
{
Try
{
Using (cryptostream cs = new cryptostream (FS, Des. createencryptor (btkey, btiv), cryptostreammode. Write ))
{
CS. Write (btfile, 0, btfile. Length );
CS. flushfinalblock ();
}
}
Catch
{
Throw;
}
Finally
{
FS. Close ();
}
}
}

///

/// perform DES encryption on the file content, the encrypted file overwrites the original file
///
/// absolute path of the file to be encrypted
Public void encryptfile (string sourcefile)
{< br> encryptfile (sourcefile, sourcefile);
}

/// <Summary>
/// Perform des decryption on the file content
/// </Summary>
/// <Param name = "sourcefile"> absolute path of the file to be decrypted </param>
/// <Param name = "destfile"> absolute path of the decrypted file </param>
Public static void decryptfile (string sourcefile, string destfile)
{

If (! File. exists (sourcefile ))
Throw new filenotfoundexception ("the specified file path does not exist! ", Sourcefile );

Byte [] btkey = encoding. Default. getbytes (key );
Byte [] btiv = encoding. Default. getbytes (IV );
Descryptoserviceprovider des = new descryptoserviceprovider ();
Byte [] btfile = file. readallbytes (sourcefile );


Using (filestream FS = new filestream (destfile, filemode. Create, fileaccess. Write ))
{
Try
{
Using (cryptostream cs = new cryptostream (FS, Des. createdecryptor (btkey, btiv), cryptostreammode. Write ))
{
CS. Write (btfile, 0, btfile. Length );
CS. flushfinalblock ();
}
}
Catch
{
Throw;
}
Finally
{
FS. Close ();
}
}
}

/// <Summary>
/// Perform des decryption on the file content. After decryption, the original file will be overwritten.
/// </Summary>
/// <Param name = "sourcefile"> absolute path of the file to be decrypted </param>
Public static void decryptfile (string sourcefile)
{
Decryptfile (sourcefile, sourcefile );
}

# Endregion

 

Read/write encrypted XML or TXT

# Region read and operate the Assembly (XML file)
Public static void savexml (string connenctionstring, string strkey) // write dynamic database configuration information
{
Commonclass. decryptfile (filepath );
Xmldocument Doc = new xmldocument ();
// Obtain the full path of the configuration file
String strfilename = application. startuppath + "\ assembly. xml ";
Doc. Load (strfilename );
// Find all elements named "add"
Xmlnodelist nodes = Doc. getelementsbytagname ("add ");
For (INT I = 0; I <nodes. Count; I ++)
{
// Obtain the key attribute of the current element
Xmlattribute ATT = nodes [I]. attributes ["key"];
// Determine whether the current element is a target element based on the first attribute of the element.
If (Att. value = strkey)
{
// Assign values to the second attribute of the target Element
ATT = nodes [I]. attributes ["value"];
Att. value = connenctionstring;
Break;
}
}
Doc. Save (strfilename );
Commonclass. encryptfile (filepath, filepath );
}

Public static string readxml (string strkey) // write dynamic database configuration information
{
Commonclass. decryptfile (filepath );
String tempvalues = "";
Xmldocument Doc = new xmldocument ();
// Obtain the full path of the configuration file
String strfilename = application. startuppath + "\ assembly. xml ";
Doc. Load (strfilename );
// Find all elements named "add"
Xmlnodelist nodes = Doc. getelementsbytagname ("add ");
For (INT I = 0; I <nodes. Count; I ++)
{
// Obtain the key attribute of the current element
Xmlattribute ATT = nodes [I]. attributes ["key"];
// Determine whether the current element is a target element based on the first attribute of the element.
If (Att. value = strkey)
{
ATT = nodes [I]. attributes ["value"];
Tempvalues = Att. value;
Break;
}
}
Doc. Save (strfilename );
Commonclass. encryptfile (filepath, filepath );
Return tempvalues;
}

Public static sqlconnection getxmlconn () // write dynamic database configuration information
{
Commonclass. decryptfile (filepath );
Sqlconnection conn;
String tempdatabase = "", tempserverip = "", tempuser = "", temppassword = "", tempstr = "";
Xmldocument Doc = new xmldocument ();
// Obtain the full path of the configuration file
String strfilename = application. startuppath + "\ assembly. xml ";
Doc. Load (strfilename );
// Find all elements named "add"
Xmlnodelist nodes = Doc. getelementsbytagname ("add ");
For (INT I = 0; I <nodes. Count; I ++)
{
// Obtain the key attribute of the current element
Xmlattribute ATT = nodes [I]. attributes ["key"];
// Determine whether the current element is a target element based on the first attribute of the element.
If (Att. value = "serverip ")
{
Tempserverip = nodes [I]. attributes ["value"]. value;
}
Else if (Att. value = "Database ")
{
Tempdatabase = nodes [I]. attributes ["value"]. value;
}
Else if (Att. value = "user ")
{
Tempuser = nodes [I]. attributes ["value"]. value;
}
Else if (Att. value = "password ")
{
Temppassword = nodes [I]. attributes ["value"]. value;
}
}
Doc. Save (strfilename );
Tempstr = "uid =" + tempuser + "; Pwd =" + temppassword;
Tempstr + = "; initial catalog =" + tempdatabase + "; server =" + tempserverip + ";";
Tempstr + = "Connect timeout = 30 ";
Conn = new sqlconnection (tempstr );
Commonclass. encryptfile (filepath, filepath );
Return conn;
}

# Endregion