I was working on a project recently that required unique API keys to be generated for clients connecting to the server. For various reasons, I settled on the style of license key you commonly see for software packages. You know, the kind you always had to read off the back of a CD case and type in when installing the application. Like H8OV7-HNTB5-JLLOH-W8FG2.

It’s fairly easy to write such a function. The basic idea is to loop around four times—once for each segment—and have a nested loop that runs five times, picking a random character each time. Here’s what I came up with:

So as you asked when the unique key generated, the user as to call you and read his code after based on the code you can generate the password as by above method. But my point of view is different, this method is not good to collaborate with user. Its waste of time that user needs to call you for password. Aug 19, 2013  7 Ways to Generate Great Ideas. Take an hour each week and go on a web journey. But that's the key to great ideas. You need to give your brain the time and space to work for you. Mirrakey can generate unique license keys based on one or more of three input parameters plus up to eight options or features. The input parameter or properties are string values that you can use for any values you require to identify your software, user or both. Jun 14, 2016  Create License key, Serial Key Maker, Generate Product Key, Validate a software License Key in C#.NET. The C# Basics beginner course is a free.

The $tokens string contains the characters that are valid in the key, so the loop can pick from it. The $segment_chars and $num_segments variables are the number of characters in a segment and the number of segments in the key, respectively. $key_string/he-master-secret-is-used-to-generate-session-keys.html. is an empty string that the loop will add the characters into.

Generate License Number

The first for loop runs four times, assuming the desired result is four segments in the key. The inner loop picks a character out of $tokens at random each time it goes around. (PHP strings are also arrays, with the each character having its own numerical offset.) The characters are tacked onto the $segment string.

Then the segment is joined with the $key_string, and a dash character is applied if the loop isn’t on the final segment yet. End result: something like H8OV7-HNTB5-JLLOH-W8FG2.

Now how can you make sure the key is unique when it’s generated?

Generate Unique License Keys For Each Sale Of Car

You generate a new key string with the function, check to see if it exists in your database, and lather/rinse/repeat until that is no longer the case. Usually you won’t have collisions too often, so it will only need to run once. I’m too lazy to figure out the probability, but considering there are 52,521,875 possible combinations for one 5-character segment…you’re probably not going to run into performance issues anytime soon. And if you do, just add another segment onto your key strings.