如何将 Struts 2 动作类中的 InputStream 值传递给 JSP 页面中的 Ajax 并将该值转换为 JSON 数组

This is my method in Action class:

private InputStream inputStream;

/* getter and setter*/

public String getClientMilestone() throws DAOTransientException, DBConfigException{
        PaymentScheduleDao paymentScheduleDao = new PaymentScheduleDao();
        List <PaymentMilestone> paymentScheduleInfo = paymentScheduleDao.getClientMilestoneInfo(projectId);
        String result = "[";

        for(int i=0; i<paymentScheduleInfo.size(); i++){
            
            result += "{"+"'"+"item"+i+"' : {"+ "'"+"milestoneName"+ "'"+":"+"'"+paymentScheduleInfo.get(i).getMilestone_name()+"'"+"}"+"},";
            
        }
        result += "]";
        System.out.println("result is "+result);
        inputStream = new StringBufferInputStream(result);
        return "success";
    }

打印如下:

result is [{'item0' : {'milestoneName':'milestone 1'}},{'item1' : {'milestoneName':'milestone 2'}}]

struts.xml:

<package name="ClientMilestone" namespace="/" extends="struts-default">
        <action name="getClientMilestone" class="packageName.PaymentScheduleAction" method="getClientMilestone">
            <result name="success" type="stream">
            <param name="contentType">text/html</param>
            <param name="inputName">inputStream</param>
            </result>
            <result name="failure">./LandingPage.jsp</result>
            <result name="error">./Error.jsp</result>
        </action>
    </package>

JSP 中的 JavaScript 函数:

function createOrViewPs() {
    
    var projectId = document.getElementById("projectId").value;
    $.ajax({ 
        method: "GET",
        url: "getClientMilestone",
        data: {"projectId" : projectId},
        traditional: true, 
        success:
            function(result){
                var jsonArr = result;
            
                for (var i=0; i<jsonArr.length; i++)
                    for (var name in jsonArr[i]) {
                        alert("Item name: "+name);
                        alert("Source: "+jsonArr[i][name].milestoneName);
                }
            },
        error: 
            function(){
                alert("fail");
            }
    });         
} 

推荐答案

因为你从服务器返回了 JSON 的字符串化版本，结果类型为 stream(注意，流结果类型可能不是合适，见下文)，您需要使用 JSON.parse() 如果你使用 jQuery，最好使用 $.each

var jsonArr = JSON.parse(result);
$.each (jsonArr, function(index, value){
  $.each (value, function(key, value){
    console.log("Item name: "+key);
    console.log("Source: "+value.milestoneName);
  });
});