I am trying to match the string 6c81748b9239e96e it's random each time. Using the following code below. My problem is that it matches the entire string and I only need the random string that contains the letters and numbers.
String
<a href="playgame.aspx?gid=4&tag=6c81748b9239e96e">Play</a>
javascript regex
string.match(/\&tag\=[A-Za-z0-9]+\"\>/i);
Here is my suggestion:
Add the snippet provided by @Artem Barger to your code: https://stackoverflow.com/a/901144/851498 You need to slightly modify it, though (adding the str argument):
function getParameterByName( name, str )
{
name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
var regexS = "[\\?&]" + name + "=([^&#]*)";
var regex = new RegExp(regexS);
var results = regex.exec( str );
if(results == null)
return "";
else
return decodeURIComponent(results[1].replace(/\+/g, " "));
}
Use it this way:
var str = getParameterByName( 'tag', string );
Jsfiddle demo: http://jsfiddle.net/Ralt/u9MAv/
You could use Regular Expression Groups to match, and later access the pattern you are after. The regex you will need to use is like so: /\&tag\=([A-Za-z0-9]+)\"\>/i. The round brackets (( and )) will denote the group you want to capture. You can then access the capture group as shown here.
EDIT: Upon closer inspection it seems that you might be using an incorrect regular expression. I am not really used to Javascript regexes but it seems that you are escaping the & and = and>, which is not required. Try this instead: /&tag=([A-Za-z0-9]+)\">/i.
var myregexp = /(&tag=)([A-Za-z0-9]+)\b/img;
var match = myregexp.exec(subject);
while (match != null) {
for (var i = 0; i < match.length; i++) {
// matched text: match[i]
}
match = myregexp.exec(subject);
}
Your regex
&tag=([A-Za-z\d]+)"
It's simplified (you escaped too much) and parenthesis were added to put the thing you want in group 1
In javascript this becomes
var myregexp = /&tag=([A-Za-z\d]+)"/;
var match = myregexp.exec(subject);
if (match != null) {
result = match[1];
} else {
result = "";
}
Explanation
Match the characters “&tag=” literally «&tag=»
Match the regular expression below and capture its match into backreference number 1 «([A-Za-z\d]+)»
Match a single character present in the list below «[A-Za-z\d]+»
Between one and unlimited times, as many times as possible, giving back as needed (greedy) «+»
A character in the range between “A” and “Z” «A-Z»
A character in the range between “a” and “z” «a-z»
A single digit 0..9 «\d»
Match the character “"” literally «"»
