W3School TIY Editor
W3School 在线教程
改变方向
暗黑模式
运行代码
<!DOCTYPE html> <html> <body> <p>单击按钮可将不同的数字四舍五入为最接近的整数。</p> <button onclick="myFunction()">试一试</button> <p id="demo"></p> <script> function myFunction() { var a = Math.round(2.60); var b = Math.round(2.50); var c = Math.round(2.49); var d = Math.round(-2.60); var e = Math.round(-2.50); var f = Math.round(-2.49); var x = a + "<br>" + b + "<br>" + c + "<br>" + d + "<br>" + e + "<br>" + f; document.getElementById("demo").innerHTML = x; } </script> </body> </html>