1.函数的定义和使用:
<!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>if...else </title> <script type="text/javascript"> var ticket = true; if (ticket) { document.write("有票,看电影") } else{ document.write("没有票,看不了电影") } function add(a,b) { var sum = 0; sum = a + b; alert(sum); } add(4,3); add(2,4); alert(5,7); </script> </head> <body> </body> </html>
2.函数的调用:
<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>函数调用</title> <script type="text/javascript"> function tcon() { alert("恭喜你学会函数调用了!"); } </script> </head> <body> <form> <input type="button" value="点点我" onclick="tcon()"> </form> </body> </html>
3.函数的返回值:
<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>返回值函数</title> <script type="text/javascript"> function app2(x,y) { var sum,x,y; sum = x * y; return sum; } var req1 = app2(5,6); var req2 = app2(2,3); var sumq = req1 + req2; document.write("req1的值:"+req1+"<br/>"); document.write("req2的值:"+req2+"<br/>"); document.write(req1+"与"+req2+"和:"+sumq); </script> </head> <body> </body> </html>