Let’s talk about mobile verification code where we need to send a six digit random string to the user device for verify his/her mobile number. In this case it is wise to generate the random string using client script (JavaScript or Jquery) & can send a copy to the server using Ajax post method.
In the below example I created a function where you can generate any length of random string from the specific characters you want. In the configuration variable of randomString() function I declared chars as the list of characters you want for your random string. Here for a demo purpose I added numbers (0 to 9) & alphabets in both the case (Upper & Lower). Using the variable string_length you can set the length of your random string. In body part of HTML I have a button control with a div DisplayRandomString. Onclick of button Generate I am applying html to the div using Jquery. randomString() function returns randomstring variable as string. Which I am showing in the div on click event of button btnGenerate.
To run the below example copy the html codes into a notepad file. Save it as html. The jquery library I referred here is a CDN link. Before run the html file make sure you are with Internet Connectivity.
Generate Random String Example
<html> <head> <script src="http://code.jquery.com/jquery-1.10.2.js"></script> <script type="text/javascript"> $(document).ready(function() { /*Generate button Click event*/ $('#btnGenerate').click(function() { $('#DisplayRandomString').html(randomString()); }); /*Function to Generate Random String*/ function randomString() { /*Charecters you want to use for your Random String*/ var chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXTZabcdefghiklmnopqrstuvwxyz"; /*Length of the Random String you want to Generate*/ var string_length = 6; var randomstring = ''; for (var i = 0; i < string_length; i++) { var rnum = Math.floor(Math.random() * chars.length); randomstring += chars.substring(rnum, rnum + 1); } return randomstring; } }); </script> </head> <body> <button id="btnGenerate">Generate</button> <!--Div to Display Random String--> <div id="DisplayRandomString"></div> </body> </html>