点击运行
<!DOCTYPE html> <html> <body> <h2>JavaScript const</h2> <p>您无法更改原始值。</p> <p id="demo"></p> <script> try { const PI = 3.141592653589793; PI = 3.14; } catch (err) { document.getElementById("demo").innerHTML = err; } </script> </body> </html>
运行结果
