As mentioned in my regular expressions tutorial (parts 1 (https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sap.km.cm.docs/library/abap/express%20you...),[ 2 | https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sap.km.cm.docs/library/abap/express%20you...] and
3), I’m more than happy that regular expressions – despite being a relatively old technology – have finally been incorporated into ABAP as of Netweaver 2004s. In the last part of my tutorials I reviewed some of the tools that are available in order to make and test regular expressions. If you are a seasoned DIY person, you might want to do it yourself. There is a DIY show –in fact it’s a commercial in disguise - on our regional TV where the handy man (called Roger) always says: “What you do yourself is usually done better”. I won’t go into the issue of whether that’s true or not though.
Pure client<br>
Anyway, there are several methods for testing your regular expressions. For me, as a web developer, it’s a foregone conclusion that it needs to be via a web application. You can make a mix of ABAP and HTML(B), but I won’t go that far for this simple application. It can easily be done via plain JavaScript. All you need is a form:</p>
<p>The RE itself</p>
<pre>Regular expression: <input type="text" name="regex" size="75" /><br></pre>
<pre> </pre>
<p>The string we want to test</p>
<pre>String to test: <input type="text" name="teststring" size="100" /><br></pre>
<pre> </pre>
<p>The modifiers</p>
<pre>All ocurences <input type="checkbox" name="global" value="g" /> </pre>
<pre>Case insensitive <input type="checkbox" name="insensitive" value="i" /><br></pre>
<p>And some JavaScript to test the RE.</p>
<p>Test whether we checked some of the modifiers</p>
<pre>
if (document.regextest.global.checked)
modifier += "g";
if (document.regextest.insensitive.checked)
modifier += "i";</pre>
<p>Create an RE object with the constructor</p>
<pre> var regex = new RegExp(document.regextest.regex.value,modifier);</pre>
<p>Execute that RE against the string</p>
<pre> var matchRE = regex.exec(document.regextest.teststring.value);</pre>
<p>As long as we find results</p>
<pre>
while ((matchRE = regex.exec(document.regextest.teststring.value))!= null)
</pre>
<p>We add the position and the found match in the message </p>
<pre> msg += "
at " + matchRE.index + "
for "+matchRE;</pre>
<p> </p>
<p>Putting it all together, it comes down to this code.</p>
<pre><html>
<head>
<title>RE tester</title>
<SCRIPT LANGUAGE="JavaScript">
function isMatch()
{
var modifier = "";
if (document.regextest.global.checked)
modifier += "g";
if (document.regextest.insensitive.checked)
modifier += "i";
regex = new RegExp(document.regextest.regex.value,modifier);
var matchRE;
var msg = "";
while ((matchRE = regex.exec(document.regextest.teststring.value))!= null)
{
msg += "
at " + matchRE.index + "
for "+matchRE;
}
if (msg != null)
{
alert("Yes, it matches" + msg);
}
else
{
alert("No, it doesn't match");
}
}
</SCRIPT>
</head>
<body>
<form name="regextest">
Regular expression: <input type="text" name="regex" size="75" /><br>
String to test: <input type="text" name="teststring" size="100" /><br>
All ocurences <input type="checkbox" name="global" value="g" />
Case insensitive <input type="checkbox" name="insensitive" value="i" /><br></pre>
<pre> <input type="button" value="Does it match?" onclick="isMatch()" />
</form>
</body>
</html></pre>
<p> </p>
<p>The result looks like this. </p>
<p><p>!https://weblogs.sdn.sap.com/weblogs/images/19902/re_js.jpg|height=231|alt=image|width=475|src=https:...!</body>
