JSFiddle - React, Tailwind, and code Playground

by S Venkatesh

HTML

<!DOCTYPE html>
<html>
<body onload="onLoad()">

<h2>Previous / Next URL - Try it out!</h2>

<button onclick="previousUrl()">Previous Url</button>
<button onclick="nextUrl()">Next Url</button>

<p id="demo"></p>

<script>
var url = 'http://www.siram.com/test01/001/test0001.html';

function onLoad() {
  document.getElementById("demo").innerHTML = url;
}

function nextUrl() {
    this.str = this.str || url; 
    var txt = str.replace(/(\d+)(?!.*\d)/, function(s) {
        var beforeAddlen = s.length;
        s = parseInt(s) + 1;
        var afterAddLen = s.toString().length;
        if (afterAddLen < beforeAddlen) {
           for (var i = 0; i < beforeAddlen - afterAddLen; i++ ) {
             s = '0' + s;
           }
        }
        return s;
    });
    document.getElementById("demo").innerHTML = txt;
    this.str = txt;
}

function previousUrl() {
  this.str = this.str || url; 
  var txt = str.replace(/(\d+)(?!.*\d)/, function(s) {
    var beforeLength = s.length;
    var updatedVal = parseInt(s) - 1;
    if (updatedVal > 0) {
      var afterLength = updatedVal.toString().length;
      if (afterLength < beforeLength) {
        for (var i = 0; i < beforeLength - afterLength; i++) {
          updatedVal = '0' + updatedVal;
        }
      }
      s = updatedVal;
    }
    return s;
  });
  document.getElementById("demo").innerHTML = txt;
  this.str = txt;
}


</script>

</body>
</html>