Regular expression in javascript

The regular expression is an object that describes pattern of characters that is used to match the character combination of strings.

Example:

<script type="text/javascript">

    function processString() {

        // Clear the txtResult element

       document.getElementById("txtResult").value = "";

        // Retrieve the user intput fromthe textbox

        var inputString = document.getElementById("txtInput").value;

        // Regular expression should be in2 forward slashes //

        // Letter g at the end of theregular expression performs a global match

        // match() method returns allsubstrings that match the given regular expression

        var result = inputString.match(/\d+/g);

       alert(result);

        if (result != null) {

            // Add the retrieved numbers tothe txtResult element

            for (var i = 0; i <result.length; i++) {

               document.getElementById("txtResult").value += result[i] + "\r\n";

            }

        }

    }

</script>

<h2>Regular expression in javascript</h2>

 <table style="border:1px solid black;">
    <tr>
        <td>Enter inputstring</td>
        <td>
          <input type="text" id="txtInput" style="width:250px" />
        </td>
    </tr>
    <tr>
        <td>click button to extract</td>
        <td>
         <input type="button" value="extract" onclick="processString()" />
        </td>
    </tr>
    <tr>
        <td>Result</td>
        <td>
          <textarea id="txtResult" rows="4" cols="30"></textarea>
        </td>
    </tr>
</table>

If input string contains words and numbers from that we want to extract all numbers.

Input:

$5,500 per square feet

Output:

Note: if you want to extract character just change the javascript code as inputString.match(/\w+/g);.