java 使用ajax调用Struts 2动作，直接向响应写入字符串不返回字符串
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Call a Struts 2 action using ajax, which write a string directly to the response does not return the string
提问by Harshana
In a struts2 application I am calling a Ajax request in and write a string directly to the response as below and return nullin the execute method of the action.
在 struts2 应用程序中，我正在调用 Ajax 请求并将字符串直接写入响应，如下所示，并null在操作的执行方法中返回。
ServeletActionContext.getResponse().getOutputStream().print("sample string");
return null;
In struts.xmlI have the below declaration, (below is how the application declares the actions with result types which are working fine. In my case since I don't need result to invoke a JSP or another action, I did not add the result tag)
在struts.xml我有以下声明，（以下是应用程序如何声明具有正常工作的结果类型的操作。在我的情况下，由于我不需要结果来调用 JSP 或其他操作，我没有添加结果标记）
<action name="controller" class="controller">
And I map the section class in the application-context.xml
我将部分类映射到 application-context.xml
<bean id="controller" class="com.test.ControllerAction" scope="prototype">
Then I have the ajax call as below,
然后我有如下的ajax调用，
$.ajax({url:"/root/me/controller.action",success:function(result){
alert(result);
}});
But the problem is in above instead of alerting the "sample string"which I wrote for the response, it alerts the whole JSP page where the above Ajax call resides. What am I missing here?
但问题出在上面，而不是提醒"sample string"我为响应编写的内容，而是提醒上述 Ajax 调用所在的整个 JSP 页面。我在这里错过了什么？
回答by Roman C
Return result type streamby default it outputs text.
返回结果类型stream默认输出文本。
<action name="controller" class="ControllerAction">
<result type="stream">
<param name="contentType">text/html</param>
<param name="inputName">stream</param>
</result>
</action
streamshould be the property type ImputStream;
stream应该是属性类型ImputStream；
public class ControllerAction extends ActionSupport {
private InputStream stream;
//getter here
public InputStream getStream() {
return stream;
}
public String execute() throws Exception {
String str = "sample string";
stream = new ByteArrayInputStream(str.getBytes());
return SUCCESS;
}
}
回答by sithum
Instead of using
而不是使用
ServeletActionContext.getResponse().getOutputStream().print("sample string");
return null;
use this code
使用此代码
PrintWriter out = response.getWriter();
out.write("sample string");
return null;
This should work.
这应该有效。
