window.onload = preAddress;
应该可以工作这是一个demo，以及完整的代码：
<!DOCTYPE html><html> <head> <title>Test</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <script type="text/javascript"> function preAddress() { alert('ok'); } window.onload = preAddress; </script> </head> <body> </body></html>
<!DOCTYPE html><html> <head> <title>Test</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <script type="text/javascript"> function preAddress() { alert('ok'); } </script> </head> <body onload="preAddress();"> </body></html>
