Eclipse 为什么HtmlButton object.click（）在HtmlUnit中不起作用？

我从一个html+javascipt页面获得了htmlbutton，但我的代码不起作用（Eclipse中的JUnit+HtmlUnit） 代码是：

final HtmlPage page = (HtmlPage)webClient.getPage(url);
final HtmlForm form = page.getFormByName("registrationForm");
final HtmlButton button=(HtmlButton)page.getElementById("submit1"); 

final HtmlTextInput phone = form.getInputByName("phoneno");

phone.setValueAttribute("1234567890");

// Now submit the form by clicking the button and get back the second page.

final HtmlPage page2 = button.click();  //this doesn't work
final String pageAsXml = page2.asText();
System.out.println(pageAsXml);

行注释“这不起作用”有一些问题。没有错误，但它不起作用。 webclient构造函数有什么问题吗？是否需要将浏览器版本指定为参数？这在eclipse中有效吗

final HtmlPage page = (HtmlPage)webClient.getPage(url);
final HtmlForm form = page.getFormByName("registrationForm");
final HtmlButton button=(HtmlButton)form.getElementById("submit1"); 
//instead of page try using the form
final HtmlTextInput phone = form.getInputByName("phoneno");

phone.setValueAttribute("1234567890");

// Now submit the form by clicking the button and get back the second page.

final HtmlPage page2 = button.click();  //this doesn't work
final String pageAsXml = page2.asText();
System.out.println(pageAsXml);

//Let me know if it works.