(Visual FoxPro) Encrypting and Decrypting Content

Demonstrates how to encrypt and decrypt the content of an XML node using 128-bit CBC AES encryption.

The input XML, available at http://www.chilkatsoft.com/data/fox.xml, is this:

<root>
    <fox1>The quick brown fox jumps over the lazy dog</fox1>
    <fox2>The quick brown fox jumps over the lazy dog
        <child1>ABC</child1>
        <child2>XYZ</child2>
    </fox2>
</root>

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL loXml
LOCAL lnSuccess

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Xml')
loXml = CreateObject('Chilkat.Xml')

* The sample input XML is available at http://www.chilkatsoft.com/data/fox.xml
lnSuccess = loXml.LoadXmlFile("fox.xml")
IF (lnSuccess <> 1) THEN
    ? loXml.LastErrorText
    RELEASE loXml
    CANCEL
ENDIF

* Navigate to the "fox1" node, which is the 1st child:
lnSuccess = loXml.FirstChild2()

* Encrypt the content:
lnSuccess = loXml.EncryptContent("myPassword")

* Navigate back to the root:
loXml.GetRoot2()

* Examine the new XML document:
? loXml.GetXml()

* This is the XML w/ the encrypted content:
* <root>
*     <fox1>1hTtf7XmO+78H+OIr5eWHIuXxP78KPeYrZbsD0HX4negO9ZRqYMBY4s46sPNp+Q+
*     </fox1>
*     <fox2>The quick brown fox jumps over the lazy dog
*         <child1>ABC</child1>
*         <child2>XYZ</child2>
*     </fox2>
* </root>

* Now decrypt and show that the original content was restored:
lnSuccess = loXml.FirstChild2()
lnSuccess = loXml.DecryptContent("myPassword")
loXml.GetRoot2()
? loXml.GetXml()

* Now encrypt the content of the "fox2" node.
* First navigate to the "fox2" child.
lnSuccess = loXml.FindChild2("fox2")
lnSuccess = loXml.EncryptContent("myPassword")
loXml.GetRoot2()
? loXml.GetXml()

* This is the XML w/ the "fox2" encrypted content:

* <root>
*     <fox1>The quick brown fox jumps over the lazy dog</fox1>
*     <fox2>1hTtf7XmO+78H+OIr5eWHIuXxP78KPeYrZbsD0HX4negO9ZRqYMBY4s46sPNp+Q+
* 
*         <child1>ABC</child1>
*         <child2>XYZ</child2>
*     </fox2>
* </root>

* Notice that the *content* of the node is encrypted.  The child nodes are NOT encrypted.
* This is intentional.  To encrypt the content + the subtrees rooted at a given node, 
* one would call ZipTree to transform the content and subtrees
* to Base64-encoded compressed content, and then call
* EncryptContent to encrypt.

* Finally, decrypt the "fox2" content:
lnSuccess = loXml.FindChild2("fox2")
lnSuccess = loXml.DecryptContent("myPassword")
loXml.GetRoot2()
? loXml.GetXml()

RELEASE loXml