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Result
JavaScript
HTML

$(document).ready(function () {
                $("#replaceAll").click(function () {
                    $("b").replaceAll("p");
                });
                $("#replaceWith").click(function () {
                    $("p").replaceWith($('b'));
                });
            });

<html>
        <head>
        <title>replaceAll</title>
        </head>
        <body>
        <b>This content will replace all paragraph element's content on click of Replace All button.</b>
        <p>This is 99codingexamples.</p><br />
        <p>This is demo for replaceAll method.</p><br />
        <p>Jquery is amazing.</p><br />
        <input type="button" id="replaceAll" value="Replace All"/>
        <input type="button" id="replaceWith" value="Replace With"/>
        <input type="button" id="reset" value="Reset" onclick="location.reload()" />
        </body>
        </html>