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  • Error handling
  • Operating mode in Windows Vista (and later)
  • Encrypting/Decrypting a character string
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Warning
From version 24, fCrypt is kept for backward compatibility. This function has been replaced with fEncrypt.
Encrypts a file in binary or ASCII format.
Remark: This file can be decrypted by fDecrypt.
WEBDEV - Server codeAjax
// Encrypt a file
ResEncrypt = fEncrypt("C:\MyDirectories\File.txt", "C:\MyDirectories\EncryptedFile.txt", "Password")
Syntax
<Result> = fEncrypt(<Path of file to encrypt> , <Path of encrypted file> , <Password> [, <Type of encryption> [, <Format of encrypted file>]])
<Result>: Boolean
  • True if the encryption was performed,
  • False otherwise. To get more details on the error, use ErrorInfo with the errMessage constant.
<Path of file to encrypt>: Character string
Name and full (or relative) path of the file to encrypt (up to 260 characters). A UNC path can be used.
WindowsLinux This parameter can be in Ansi or Unicode format.
<Path of encrypted file>: Character string
Name and full (or relative) path of the encrypted file (up to 260 characters). A UNC path can be used.
WindowsLinux This parameter can be in Ansi or Unicode format.
<Password>: Character string
Password used to encrypt the file. This password will be used to decrypt the encrypted file (fDecrypt). A long password provides better encryption security.
<Type of encryption>: Optional constant
Indicates the type of encryption:
cryptFast
(Default value)
Priority is given to the encryption speed (algorithm on 128 bits).
PHP The algorithm used will be a Blowfish algorithm with 16 rounds.
cryptNoneNo encryption is performed.
cryptRC516Priority is given to the encryption security (RC5 algorithm on 16 rounds).
PHP This constant has no effect.
cryptSecurePriority is given to the encryption security (RC5 algorithm on 128 bits).
PHP The algorithm used will be a 128-bit RIJNDAEL algorithm.
<Format of encrypted file>: Optional Integer constant
Indicates the format of the encrypted file:
encodeBASE64BASE 64 format.
The file is encrypted with the BASE64 algorithm. The encrypted file will be larger (about 30%) than the initial file.
This format can be used to insert an encrypted file into the email body for example.
encodeNone or FalseBinary format.
The encrypted file may contain non-printable characters. The file will be larger (about 4 bytes) than the initial file.
encodePCS or True
(Default value)
ASCII format.
The encrypted file will contain printable characters only. The encrypted file will be larger (about 30%) than the initial file.
This format can be used to insert an encrypted file into the email body for example.
encodeUUEncodeUUEncode format.
The file is encrypted with the UUEncode algorithm. The encrypted file will be larger (about 30%) than the initial file.
This format can be used to insert an encrypted file into the email body for example.

Remarks

Error handling

fEncrypt throws an error in the following cases:
  • the file to encrypt does not exist,
  • the file to encrypt is locked,
  • the path of the file to encrypt is invalid,
  • <Password> is an empty string,
  • the user has no read rights on the file to encrypt,
  • the user has no write rights on the encrypted file.
WEBDEV - Server code

Operating mode in Windows Vista (and later)

If this function does not operate properly in Windows Vista (and later), check whether the file or directory used is not in one of the system directories (Windows directory or "Program Files" directory).
In Windows Vista (and later), with the UAC mechanism (User Account Control) enabled, you must have administrator privileges to handle and/or modify the files or directories in system directories (Windows directory or "Program Files" directory).
Programming tip: To handle and/or modify the files or directories without administrator privileges, you should:
  • avoid writing to the Windows directory or to the "Program Files" directory,
  • use the system directory of the application (returned by SysDir with the srAppDataCommun constant, for example).
Remark: In Windows Vista (and later), the virtualization mechanism is used to make the applications compatible with Vista. If the file is created in a system directory without having sufficient rights, this file will actually be created in another directory (C:\Users\<LOGIN>AppData\Local\VirtualStore\Windows\). In this case, the file cannot be shared between several applications.

Encrypting/Decrypting a character string

To encrypt/decrypt a character string, use Encrypt and Decrypt.
PHP Encryption in PHP
In PHP, the BlowFish encryption (cryptFast constant) and the RINJDAEL encryption (cryptSecure constant) are based on the MCrypt library. This library is commonly used by the PHP hosting companies and therefore it is always enabled. This library can be downloaded from the PHP site.
To enable (if necessary) this library locally, the following elements are required:
  • PHP installed.
  • the PHP.INI file found in the Windows directory must include the "extension=php_mcrypt.dll" line.
  • the php_mcrypt.dll file must exist in the directory of PHP extensions. This directory is defined in the PHP.INI file by the "extension_dir" variable.
Related Examples:
The encryption functions Unit examples (WINDEV): The encryption functions
[ + ] Using the encryption/decryption functions of WINDEV.
This example is used to:
- Encrypt a character string
- Decrypt a character string
The encryption functions Unit examples (WINDEV Mobile): The encryption functions
[ + ] Using the WLanguage encryption and decryption functions.
This example is used to:
- Encrypt a character string
- Decrypt a character string
Component: wd290std.dll
Minimum version required
  • Version 9
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Last update: 07/04/2023

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