源代码
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>享学课堂</title> </head> <body> <p id="demo"></p> <script> var x = 5; // Initialize x var y; // Declare y elem = document.getElementById("demo"); // Find an element elem.innerHTML = x + " " + y; // Display x and y y = 7; // Assign 7 to y </script> </body> </html>
运行结果