我如何使用spring将对象从jsp传递到控制器

Question

I have a class User and a class Project wich has an arraylist with users. I have a Project page with a list of all my projects and when i click on one, it takes me to the page of that project by sending the id of that project in the url.

On my detail project page i want to add users that i created. The users are displayed on a modal in a table with a button to add them.

<div class="modal fade" id="myModal" role="dialog">
        <div class="modal-dialog">
            <!-- Modal content-->
            <div class="modal-content">
                <div class="modal-header">
                    <button type="button" class="close" data-dismiss="modal">&times;</button>
                    <h4 class="modal-title"></h4>
                </div>
                <div class="modal-body">
                    <h1 class="text-center">UserList</h1>
                    <br><br>
                    <table class="table table-hover">
                        <thead>
                            <tr>
                                <th>Photo</th>
                                <th>Firstname</th>
                                <th>Lastname</th>
                                <th>Function</th>
                                <th>Email</th>
                            </tr>
                        </thead>
                        <tbody>
                            <c:forEach var="u" items="${users}">
                                <tr>
                                    <td><img src="${u.getPhoto()}"
                                             alt="Alternate Text" class="img-responsive" /></td>
                                    <td>${u.getFirstname()}</td>
                                    <td>${u.getLastname()}</td>
                                    <td>${u.getFunction()}</td>
                                    <td>${u.getEmail()}</td>
                                    <td><Button type="Button" class="btn btn-default">Add</button></td>
                                </tr> 
                            </c:forEach>
                        </tbody>
                    </table>
                </div>
            </div>
        </div>
    </div>

My question is how do i send the id of the user and the id of the project i want them to be added to my controller?

I know i can pass an id with the url but i dont want to open a new page.

I want to send the ID of the user and the project to my controller by clicking on the add button to my controller so i can use those in my method called addUserToProject()

Answer 1

在呈现的页面上，您只有两个选项，要么进行常规表单发布，要么如果不想打开新的URL，请使用Ajax。

Answer 2

JSP

First, make a hidden input with selected project id, so you can get it later:

<input type="hidden" id="currentProjectId" value="12">

Second, set attribute name of add buttons equal userId :

<td><Button type="Button" name="${u.getId()}" class="btn btn-default">Add</button></td>

Javascript:

Define onclick linstener for each "add button" and get the current user id from the button:

   $(".btn").click(function(event) {
         event.preventDefault();

         var currentProjectId= $('#currentProjectId').val();
         var userId = $(this).attr("name");

        addUser(currentProjectId, userId);

    });

Make ajax request and post the ids to controller:

function addUser(currentProjectId, selectedUserId) {

    $.ajax({
        type : "POST",
        contentType : "application/json",
        url : "/addUserToProject",
        data :{ projectId: currentProjectId, userId: selectedUserId}, 
        dataType : 'json',
        timeout : 100000,
        success : function(data) {
            console.log("SUCCESS: ", data);
        },
        error : function(e) {
            console.log("ERROR: ", e);
            display(e);
        },
        done : function(e) {
            console.log("DONE");
        }
    });
}

Finally, controller accepts ids using @RequestParam:

@RequestMapping(value = "/addUserToProject", method = RequestMethod.POST,produces = MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody
String Submit(@RequestParam("projectId") Integer projectId ,@RequestParam("userId ") Integer userId ) {

   //insert user

    return "ok";
}