Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<body>

<p>Click one of the buttons to perform a search for the characters "THIS" in a string.</p>

<button onclick="myFunction()">Global case-sensitive search</button>
<button onclick="myFunction2()">Global case-insensitive search</button>

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

<script>
function myFunction() {
    var str = "THIS This this";
    var patt1 = /[THIS]/g;
    var result = str.match(patt1);
    document.getElementById("demo").innerHTML = result;
}
</script>

<script>
function myFunction2() {
    var str = "THIS This this";
    var patt1 = /[THIS]/gi;
    var result = str.match(patt1);
    document.getElementById("demo").innerHTML = result;
}
</script>

</body>
</html>