Regular expressions in AX

In computing, a regular expression is a string that is used to describe or match a set of strings, according to certain syntax rules.

 

Regular expressions are used by many text editors and utilities to search and manipulate bodies of text based on certain patterns. Many programming languages support regular expressions for string manipulation. For example, Perl and Tcl have a powerful regular expression engine built directly into their syntax. The set of utilities (including the editor ed and the filter grep) provided by Unix distributions were the first to popularize the concept of regular expressions. "Regular expression" is often shortened in speech to regex, and in writing to regexp or regex (singular) or regexps, regexes, or regexen (plural).

 

As an example of the syntax, the regular expression \bex can be used to describe (and search for) all of the instances of the string "ex" that occur at word breaks (signified by the \b). Thus in the phrase, "Texts for expert experimenters," the regular expresssion \bex returns the "ex" in "expert" and "experimenters," but not in "Texts" (because the "ex" occurs inside the word there and not at the word break).

 

Many modern computing systems provide wildcard characters in matching filenames from a file system. This is a core capability of many command-line shells and is known as globbing. Wildcards differ from regular expressions in that they can only express very restrictive forms of alternation.

 

[Source for this text: www.wikipedia.org]

 

In AX too we can make use of regular expressions. Here is a sample code which can be used to validate an email address. Just copy this method to the "Global" class in your application. Please note this code will work only on AX 4.0 and above

static boolean validateEmailAddress(str 100 _str)

{

    boolean retval;

    InteropPermission permission;

    System.Text.RegularExpressions.Regex re;

    ;

 

    permission = new InteropPermission(InteropKind::ClrInterop);

    permission.assert();

 

    // BP deviation documented

    re = new System.Text.RegularExpressions.Regex("^([a-zA-Z0-9_’+*$%\^&!\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9:]{2,4})+$");

 

    // BP deviation documented

    retval = CLRInterop::getAnyTypeForObject(re.IsMatch(_str));

 

    return retval;

}

 

Here is a sample job which makes use of above written method.

 

static void checkEmailAddress(Args _args)

{

    str emailaddress = "sumit.l@sumit.l.com";

    ;

    print validateEmailAddress(emailaddress);

    pause;

}