i am newbie to regex in javascript and i got stuck in using regex in javascript.
I have two scenerio
1) I have a string like aaa/+/bbb/+ , i want to match this string with strings aaa/1/bbb/hello123 and aaa/1/bbb/ using regex and both should return true. If i pass aaa/1/bbb then it should give false
2) If i have string aaa/# then it should match all the above strings and returmn true
Can any one help me?
In regex, the + would translate to [^/]*, and the # would translate to .*.
The next step is to escape special characters in the input string. This regex has that purpose. Since the + is a special character, we will have to unescape manually.
RegExp.escape= function(s) {
return s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
};
function matchesPattern(pattern, input) {
pattern = RegExp.escape(pattern); // escape special characters
pattern = pattern.replace(/\\\+/g, "[^/]*"); // replace '\+'
pattern = pattern.replace(/#/g, ".*"); // replace '#'
pattern = new RegExp("^" + pattern + "$"); // construct regex
return pattern.test(input); // test input
}
console.log(matchesPattern("aaa/+/bbb/+", "aaa/1/bbb/hello123"));
console.log(matchesPattern("aaa/+/bbb/+", "aaa/1/bbb/"));
console.log(matchesPattern("aaa/+/bbb/+", "aaa/1/bbb"));
console.log(matchesPattern("aaa/#", "aaa/1/bbb/hello123"));
console.log(matchesPattern("aaa/#", "aaa/1/bbb/"));
console.log(matchesPattern("aaa/#", "aaa/1/bbb"));The regular expression ^aaa\/[0-9]+\/bbb\/[\w\d]*$ will match the following strings:
aaa/1/bbb/hello123
aaa/1/bbb/
These strings will not be matched:
aaa/1/bbb
I am unclear about your second scenario - are you saying that the regex should also match the string aaa/#?
You can use regex in javascript like so:
var re = /^aaa\/[0-9]+\/bbb\/[\w\d]*$/;
var matches = re.test("aaa/1/bbb/");
if (matches) { console.log("it matches!"); }
re.test(str) in order to see if there is a match.
+and#is? It looks like+is intended to match one or more numbers and letters, but it's not clear.2) If i have string aaa/# then it should match all the above strings and returmn true- no it shouldn't#shouldn't be aloud to have that meaning.aaa/#will not match the strings given. But I think I understand where I went wrong, I assumed he meant thataaa/#was actually a RegExp - re-reading the question, I see he wants someone to write some code for his own pattern matching scheme, possibly using RegExp as required - this is not icanhazcode.com so I wish him the best of luck in his quest to get free programming donei got stuck in using regex- you sure have, @Qasim, you haven't got ANY code at all - good luck