为啥document.write()又不输出了。
<!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 rep1=app2(5,6); var rep2=app2(2,3); sump=rep1+rep2; 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>