xxxxxxxxxx <html> <head> <meta charset="utf-8"> <title>W3Cschool教程(w3cschool.cn)</title> <script type="text/javascript">function getValue(){ var a,b,c; a = void ( b = 5, c = 7 ); document.write('a = ' + a + ' b = ' + b +' c = ' + c );}</script></head><body> <p>点击以下按钮查看结果：</p><form><input type="button" value="点我" onclick="getValue();" /></form> </body></html>