htmlunit jar项目路径http://sourceforge.net/projects/htmlunit/files/htmlunit/

demo代码如下

public class AutoLogin {

	/** 登录页面 */

	private static final String LOGIN_URL = "http://website/login.aspx";

	/** 任务列表页面 */

	private static final String TASK_LIST_URL = "http://website/Banli.aspx";

	/**

	 * @param args

	 * @throws Exception

	 */

	public static void main(String[] args) throws Exception {

		testHomePage();

	}

	public static void testHomePage() throws Exception {

	    final WebClient webClient = new WebClient(BrowserVersion.INTERNET_EXPLORER_8);

	    webClient.getOptions().setThrowExceptionOnScriptError(false); //此行必须要加

	    webClient.getOptions().setCssEnabled(false);

//	    webClient.getOptions().setJavaScriptEnabled(true);

//	    webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);

	    webClient.getOptions().setTimeout(300000);

	    // 获取首页

	    HtmlPage page = (HtmlPage) webClient.getPage(LOGIN_URL);

	    // 根据form的名字获取页面表单，也可以通过索引来获取：page.getForms().get(0)

	    final HtmlForm form = page.getFormByName("form1");

	    // 用户名/密码

	    HtmlTextInput textUserName = form.getInputByName("txtUserName");

	    textUserName.setText("username");

	    HtmlPasswordInput txtPwd = form.getInputByName("txtPwd");

	    txtPwd.setText("pass");

	    //调用JS触发登录按钮

	    Page page1 = page.executeJavaScript("$('#btn').click()").getNewPage();

	    page1 = webClient.getPage(TASK_LIST_URL);

	    System.out.println("*************************************************************************************");

	    System.out.println(page1.getWebResponse().getContentAsString());

	    System.out.println("*************************************************************************************");

	    System.out.println("");

	    System.out.println("Cookies : " + webClient.getCookieManager().getCookies().toString());

	}

}

　　搞不清ASP.NET内部什么逻辑，试了很多方法都不行，查看了无所网站，无意中看到一个这个配置http://stackoverflow.com/questions/20352284/scraping-aspx-page-using-htmlunit

 import java.net.MalformedURLException;

 import com.gargoylesoftware.htmlunit.BrowserVersion;

 import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;

 import com.gargoylesoftware.htmlunit.WebClient;

 import com.gargoylesoftware.htmlunit.html.HtmlElement;

 import com.gargoylesoftware.htmlunit.html.HtmlPage;

 public class teste {

     public static void main(String args[]) throws FailingHttpStatusCodeException, MalformedURLException, IOException

     {

        HtmlPage page = null;

        String url = "http://www.bmfbovespa.com.br/cias-listadas/empresas-listadas/BuscaEmpresaListada.aspx?Idioma=pt-br";

        WebClient webClient = new WebClient(BrowserVersion.FIREFOX_17);

        webClient.getOptions().setThrowExceptionOnScriptError(false);

        webClient.getOptions().setCssEnabled(false);

        webClient.getOptions().setJavaScriptEnabled(false);

        webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);

        webClient.getOptions().setTimeout(30000);

        page = webClient.getPage( url );

        System.out.println("Current page: Empresas Listadas | BM&FBOVESPA");

        HtmlElement theElement1 = (HtmlElement) page.getElementById("ctl00_contentPlaceHolderConteudo_BuscaNomeEmpresa1_btnTodas");

        page = theElement1.click();

        System.out.println(page.asText());

        System.out.println("Test has completed successfully");

     }

 }

最后测试下来，如果不加 webClient.getOptions().setThrowExceptionOnScriptError(false);就一直报这个错误

 Exception in thread "main" ======= EXCEPTION START ========

 Exception class=[java.lang.RuntimeException]

 com.gargoylesoftware.htmlunit.ScriptException: Exception invoking click

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:954)

     at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:628)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:513)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:836)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:812)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:800)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:910)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScript(HtmlPage.java:878)

     at com.suypower.AutoLogin12345.testHomePage(AutoLogin12345.java:48)

     at com.suypower.AutoLogin12345.main(AutoLogin12345.java:23)

 Caused by: java.lang.RuntimeException: Exception invoking click

     at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:181)

     at net.sourceforge.htmlunit.corejs.javascript.FunctionObject.call(FunctionObject.java:449)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1536)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:798)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.call(InterpretedFunction.java:105)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.doTopCall(ContextFactory.java:411)

     at com.gargoylesoftware.htmlunit.javascript.HtmlUnitContextFactory.doTopCall(HtmlUnitContextFactory.java:309)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3286)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.exec(InterpretedFunction.java:115)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$3.doRun(JavaScriptEngine.java:827)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:939)

     ... 9 more

 Caused by: com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot read property "nodeName" from null (http://xxxx/305000772#7)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:954)

     at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:628)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:513)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:836)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:812)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:800)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:910)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.executeInlineScriptIfNeeded(HtmlScript.java:354)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.executeScriptIfNeeded(HtmlScript.java:415)

     at com.gargoylesoftware.htmlunit.html.HtmlScript$3.execute(HtmlScript.java:271)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.onAllChildrenAddedToPage(HtmlScript.java:293)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.endElement(HTMLParser.java:799)

     at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.endElement(HTMLParser.java:756)

     at org.cyberneko.html.HTMLTagBalancer.callEndElement(HTMLTagBalancer.java:1170)

     at org.cyberneko.html.HTMLTagBalancer.endElement(HTMLTagBalancer.java:1072)

     at org.cyberneko.html.filters.DefaultFilter.endElement(DefaultFilter.java:206)

     at org.cyberneko.html.filters.NamespaceBinder.endElement(NamespaceBinder.java:330)

     at org.cyberneko.html.HTMLScanner$ContentScanner.scanEndElement(HTMLScanner.java:3126)

     at org.cyberneko.html.HTMLScanner$ContentScanner.scan(HTMLScanner.java:2093)

     at org.cyberneko.html.HTMLScanner.scanDocument(HTMLScanner.java:920)

     at org.cyberneko.html.HTMLConfiguration.parse(HTMLConfiguration.java:499)

     at org.cyberneko.html.HTMLConfiguration.parse(HTMLConfiguration.java:452)

     at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.parse(HTMLParser.java:1039)

     at com.gargoylesoftware.htmlunit.html.HTMLParser.parse(HTMLParser.java:252)

     at com.gargoylesoftware.htmlunit.html.HTMLParser.parseHtml(HTMLParser.java:198)

     at com.gargoylesoftware.htmlunit.DefaultPageCreator.createHtmlPage(DefaultPageCreator.java:271)

     at com.gargoylesoftware.htmlunit.DefaultPageCreator.createPage(DefaultPageCreator.java:159)

     at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseInto(WebClient.java:478)

     at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:352)

     at com.gargoylesoftware.htmlunit.html.BaseFrameElement.loadInnerPageIfPossible(BaseFrameElement.java:183)

     at com.gargoylesoftware.htmlunit.html.BaseFrameElement.loadInnerPage(BaseFrameElement.java:121)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.loadFrames(HtmlPage.java:1893)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.initialize(HtmlPage.java:227)

     at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseInto(WebClient.java:485)

     at com.gargoylesoftware.htmlunit.WebClient.loadDownloadedResponses(WebClient.java:2135)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.doProcessPostponedActions(JavaScriptEngine.java:982)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.processPostponedActions(JavaScriptEngine.java:1072)

     at com.gargoylesoftware.htmlunit.html.DomElement.click(DomElement.java:789)

     at com.gargoylesoftware.htmlunit.html.HtmlImageInput.click(HtmlImageInput.java:152)

     at com.gargoylesoftware.htmlunit.javascript.host.html.HTMLInputElement.click(HTMLInputElement.java:477)

     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

     at java.lang.reflect.Method.invoke(Method.java:606)

     at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:153)

     ... 19 more

 Caused by: net.sourceforge.htmlunit.corejs.javascript.EcmaError: TypeError: Cannot read property "nodeName" from null (http://xxxx/305000772#7)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.constructError(ScriptRuntime.java:3935)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.constructError(ScriptRuntime.java:3919)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.typeError(ScriptRuntime.java:3944)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.typeError2(ScriptRuntime.java:3960)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.undefReadError(ScriptRuntime.java:3971)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.getObjectProp(ScriptRuntime.java:1519)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1243)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:798)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.exec(InterpretedFunction.java:118)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$3.doRun(JavaScriptEngine.java:827)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:939)

     ... 65 more

 Enclosed exception:

 java.lang.RuntimeException: Exception invoking click

     at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:181)

     at net.sourceforge.htmlunit.corejs.javascript.FunctionObject.call(FunctionObject.java:449)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1536)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:798)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.call(InterpretedFunction.java:105)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.doTopCall(ContextFactory.java:411)

     at com.gargoylesoftware.htmlunit.javascript.HtmlUnitContextFactory.doTopCall(HtmlUnitContextFactory.java:309)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3286)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.exec(InterpretedFunction.java:115)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$3.doRun(JavaScriptEngine.java:827)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:939)

     at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:628)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:513)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:836)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:812)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:800)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:910)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScript(HtmlPage.java:878)

     at com.suypower.AutoLogin12345.testHomePage(AutoLogin12345.java:48)

     at com.suypower.AutoLogin12345.main(AutoLogin12345.java:23)

 Caused by: com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot read property "nodeName" from null (http://xxx/305000772#7)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:954)

     at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:628)

     at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:513)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:836)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:812)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:800)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:910)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.executeInlineScriptIfNeeded(HtmlScript.java:354)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.executeScriptIfNeeded(HtmlScript.java:415)

     at com.gargoylesoftware.htmlunit.html.HtmlScript$3.execute(HtmlScript.java:271)

     at com.gargoylesoftware.htmlunit.html.HtmlScript.onAllChildrenAddedToPage(HtmlScript.java:293)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.endElement(HTMLParser.java:799)

     at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.endElement(HTMLParser.java:756)

     at org.cyberneko.html.HTMLTagBalancer.callEndElement(HTMLTagBalancer.java:1170)

     at org.cyberneko.html.HTMLTagBalancer.endElement(HTMLTagBalancer.java:1072)

     at org.cyberneko.html.filters.DefaultFilter.endElement(DefaultFilter.java:206)

     at org.cyberneko.html.filters.NamespaceBinder.endElement(NamespaceBinder.java:330)

     at org.cyberneko.html.HTMLScanner$ContentScanner.scanEndElement(HTMLScanner.java:3126)

     at org.cyberneko.html.HTMLScanner$ContentScanner.scan(HTMLScanner.java:2093)

     at org.cyberneko.html.HTMLScanner.scanDocument(HTMLScanner.java:920)

     at org.cyberneko.html.HTMLConfiguration.parse(HTMLConfiguration.java:499)

     at org.cyberneko.html.HTMLConfiguration.parse(HTMLConfiguration.java:452)

     at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)

     at com.gargoylesoftware.htmlunit.html.HTMLParser$HtmlUnitDOMBuilder.parse(HTMLParser.java:1039)

     at com.gargoylesoftware.htmlunit.html.HTMLParser.parse(HTMLParser.java:252)

     at com.gargoylesoftware.htmlunit.html.HTMLParser.parseHtml(HTMLParser.java:198)

     at com.gargoylesoftware.htmlunit.DefaultPageCreator.createHtmlPage(DefaultPageCreator.java:271)

     at com.gargoylesoftware.htmlunit.DefaultPageCreator.createPage(DefaultPageCreator.java:159)

     at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseInto(WebClient.java:478)

     at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:352)

     at com.gargoylesoftware.htmlunit.html.BaseFrameElement.loadInnerPageIfPossible(BaseFrameElement.java:183)

     at com.gargoylesoftware.htmlunit.html.BaseFrameElement.loadInnerPage(BaseFrameElement.java:121)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.loadFrames(HtmlPage.java:1893)

     at com.gargoylesoftware.htmlunit.html.HtmlPage.initialize(HtmlPage.java:227)

     at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseInto(WebClient.java:485)

     at com.gargoylesoftware.htmlunit.WebClient.loadDownloadedResponses(WebClient.java:2135)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.doProcessPostponedActions(JavaScriptEngine.java:982)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.processPostponedActions(JavaScriptEngine.java:1072)

     at com.gargoylesoftware.htmlunit.html.DomElement.click(DomElement.java:789)

     at com.gargoylesoftware.htmlunit.html.HtmlImageInput.click(HtmlImageInput.java:152)

     at com.gargoylesoftware.htmlunit.javascript.host.html.HTMLInputElement.click(HTMLInputElement.java:477)

     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

     at java.lang.reflect.Method.invoke(Method.java:606)

     at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:153)

     ... 19 more

 Caused by: net.sourceforge.htmlunit.corejs.javascript.EcmaError: TypeError: Cannot read property "nodeName" from null (http://xxx/305000772#7)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.constructError(ScriptRuntime.java:3935)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.constructError(ScriptRuntime.java:3919)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.typeError(ScriptRuntime.java:3944)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.typeError2(ScriptRuntime.java:3960)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.undefReadError(ScriptRuntime.java:3971)

     at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.getObjectProp(ScriptRuntime.java:1519)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1243)

     at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:798)

     at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.exec(InterpretedFunction.java:118)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$3.doRun(JavaScriptEngine.java:827)

     at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:939)

     ... 65 more

 ======= EXCEPTION END ========

希望能帮助到你，晚安！

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