In the current release of OS/400 (V5R4 as of this writing), IBM introduced XML parsing (reading XML data) in RPG IV. But it's up to the RPG programmer to create XML. However, there are rumors that IBM may introduce XML creation in RPG IV with the next release of the operating system.
Regardless of whether you use your own routine to create XML, use the routines in RPG xTools, or wait for OS/400 V5R5 to use the native RPG IV routines, one problem that will still be there is escaping the XML.
Unlike URL-encoded strings, most data can be embedded in XML as plain text. This is true for all but five special characters that are used for XML itself. For example, what if your XML data contains the following string?
Are those tags part of the XML or part of the data in the XML? If they are part of the data in the XML, they need to be escaped. This means they need to appear as follows:
RPG provides no support for escaping XML; therefore, we need to write our own routine to escape data used in XML. The popular (and free) iSockets service program includes an ESCAPEXML subprocedure that does this for us. The ESCAPEXML subprocedure uses a simple FOR loop to escape the XML text. When it detects a less-than sign (<), a greater-than sign (>), and ampersand (&), double quotes ("), or single quotes ('), it converts them to their corresponding symbolic names.
An example of calling ESCAPEXML to escape the above example follows:
C callp escapeXML('iSeriesTV.com':myXML:
C %size(myXML)
In this example, the data is sent to ESCAPEXML, and it is then escaped and returned to the MYXML variable. The XML itself is not sent to the ESCAPEXML procedure. So before wrapping your data in XML, escape it.
Certainly, the data would normally be stored in a variable and passed on the first parameter of the ESCAPEXML procedure.
The code listed below is the actual ESCAPEXML subprocedure code from the iSockets service program, so if you're using iSockets, you don't need to key in this code.
** (C) COPYRIGHT 2006 – R. Cozzi, Jr. All Rights reserved.
** Download iSockets at www.iSockets.net
D escapeXML PI 10I 0
D szXMLIn 65535A Value Varying
D szXMLOut 65535A OPTIONS(*VARSIZE:*NOPASS:*OMIT)
D nOutLen 10I 0 Const OPTIONS(*NOPASS:*OMIT)
D i S 10I 0
D o S 10I 0
D bP1 S 10I 0
D bP2 S 10I 0
D bP3 S 10I 0
C if %Parms >= 1
C CallP IsParmOmit(bP1 : 1 : *OMIT)
C if %Parms >= 2
C CallP IsParmOmit(bP2 : 2 : *OMIT)
C if %Parms >= 3
C CallP IsParmOmit(bP3 : 3 : *OMIT)
C endif
C endif
C endif
C eval o = 1
C for i = 1 to %len(szXMLIn)
C Select
C When %subst(szXMLIn:i:1) = '<'
C eval %subst(szXMLOut:o:4) = '<'
C eval o = o + 4
C When %subst(szXMLIn:i:1) = '>'
C eval %subst(szXMLOut:o:4) = '>'
C eval o = o + 4
C When %subst(szXMLIn:i:1) = '&'
C eval %subst(szXMLOut:o:5) = '&'
C eval o = o + 5
C When %subst(szXMLIn:i:1) = '"'
C eval %subst(szXMLOut:o:6) = '"'
C eval o = o + 6
C When %subst(szXMLIn:i:1) = ''''
C eval %subst(szXMLOut:o:6) = '''
C eval o = o + 6
C other
C eval %subst(szXMLOut:o:1) = %subst(szXMLIn:i:1)
C eval o = o + 1
C endSL
C endfor
C return o
P escapeXML E
With this subprocedure from iSockets, you can escape the hassle of escaping!
Bob Cozzi is a programmer/consultant, writer/author, and software developer of the RPG xTools, a popular add-on subprocedure library for RPG IV. His book The Modern RPG Language has been the most widely used RPG programming book for nearly two decades. He, along with others, speaks at and runs the highly-popular RPG World conference for RPG programmers.
Bob Cozzi is a programmer/consultant, writer/author, and software developer. His popular RPG xTools add-on subprocedure library for RPG IV is fast becoming a standard with RPG developers. His book The Modern RPG Language has been the most widely used RPG programming book for more than a decade. He, along with others, speaks at and produces the highly popular RPG World conference for RPG programmers.
MC Press books written by Robert Cozzi available now on the MC Press Bookstore.
 |
||
 |
|
RPG TnT Get this jam-packed resource of quick, easy-to-implement RPG tips! List Price $65.00 Now On Sale
|
|
||
 |
|
The Modern RPG IV Language Cozzi on everything RPG! What more could you want? List Price $99.95
Now On Sale
|
More than ever, there is a demand for IT to deliver innovation. Your IBM i has been an essential part of your business operations for years. However, your organization may struggle to maintain the current system and implement new projects. The thousands of customers we've worked with and surveyed state that expectations regarding the digital footprint and vision of the company are not aligned with the current IT environment.
TRY the one package that solves all your document design and printing challenges on all your platforms. Produce bar code labels, electronic forms, ad hoc reports, and RFID tags – without programming! MarkMagic is the only document design and print solution that combines report writing, WYSIWYG label and forms design, and conditional printing in one integrated product. Make sure your data survives when catastrophe hits. Request your trial now! Request Now.
Forms of ransomware has been around for over 30 years, and with more and more organizations suffering attacks each year, it continues to endure. What has made ransomware such a durable threat and what is the best way to combat it? In order to prevent ransomware, organizations must first understand how it works.
Disaster protection is vital to every business. Yet, it often consists of patched together procedures that are prone to error. From automatic backups to data encryption to media management, Robot automates the routine (yet often complex) tasks of iSeries backup and recovery, saving you time and money and making the process safer and more reliable. Automate your backups with the Robot Backup and Recovery Solution. Key features include:
Business users want new applications now. Market and regulatory pressures require faster application updates and delivery into production. Your IBM i developers may be approaching retirement, and you see no sure way to fill their positions with experienced developers. In addition, you may be caught between maintaining your existing applications and the uncertainty of moving to something new.
IT managers hoping to find new IBM i talent are discovering that the pool of experienced RPG programmers and operators or administrators with intimate knowledge of the operating system and the applications that run on it is small. This begs the question: How will you manage the platform that supports such a big part of your business? This guide offers strategies and software suggestions to help you plan IT staffing and resources and smooth the transition after your AS/400 talent retires. Read on to learn:
LATEST COMMENTS
MC Press Online