<!DOCTYPE html> <html> <body> <h2>JavaScript abc</h2> <p id="demo"></p> <button onclick="zmacknutoA()">START</button> <button onclick="zmacknutoB()">STOP</button> <script> function zmacknutoA(){ a = new Date() } function zmacknutoB(){ b = new Date() document.getElementById('demo').innerHTML = (b-a)/1000 + "s" } </script> </body> </html>
Opakování
<!DOCTYPE html> <html> <body> <h2>JavaScript abc</h2> <p id="demo"></p> <button onclick="zmacknutoA()">START</button> <button onclick="zmacknutoB()">STOP</button> <script> function zmacknutoA(){ a = new Date() } function zmacknutoB(){ b = new Date() document.getElementById('demo').innerHTML = (b-a)/1000 + "s" a=null } function update(){ if(a){ b = new Date() document.getElementById('demo').innerHTML = (b-a)/1000 + "s" } } setInterval(update, 20) </script> </body> </html>