通过Ajax调用在节点服务器端获取表单数据

我正在尝试使用Ajax调用提交表单数据。相关的表单代码如下所示。

<form target="_blank" id="addCaseForm" class="form-horizontal col-md-12" action="" method="POST">
    <div class="form-group">
        <label class="col-md-3 control-label">Patient Name</label>
        <div class="col-md-9">
            <input type="text" class="form-control" id="patientName" name="patientName" placeholder="" required>
        </div>
    </div>
    .. .. .. .. ..
    <button type="submit" class="btn btn-primary  btn-xs">Save</button>
</form>

点击提交按钮后，下面的事件被调用，我正在对node.js服务器进行正常的Ajax调用以提交表单数据。首先，我序列化了表单数据，并将其作为附加参数传递给request.sent。

但是如何在服务器端获取这些数据。我尝试了多种方法来获取数据，如req.body.ppatientName、req.params（'patientName'），但都没有成功。我错过了什么。

$("#addCaseForm").submit(function(event) {
    var postData = $(this).serialize(); 
   // "patientName=rtgh&patientFatherName=5tryh&patientDob=10%2F08%2F2014&patientBloodGroup=o&patientAge=25&patientSex=M&patientNationality=Indian&patientPhone=76&Specilizationtag=3&patientDesc=uyhjn"
    event.preventDefault();
    var request;    
    try {
        request = new XMLHttpRequest();
    } catch (tryMS) {
        try {
            request = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (otherMS) {
            try {
                request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (failed) {
                request = null;
            }
        }
    }
    if (request == null) {
        console.log("Error::Unable to create request object at add new case");
        return false;
    }
    request.open('POST', '/addNewCase', true);
    request.onreadystatechange = function() {
        if (request.readyState == 4) {
            if (request.status == 200) {
                console.log("Form successfully submitted");
            }
        }
    };
    request.send(postData);
});

如何在节点服务器端获取表单数据

我正在使用快递，节点代码低于

exports.addNewCase = function(req,res){
    var Specilizationtag = [],
        attachemntTag = [];
    Specilizationtag = req.params('Specilizationtag').split(',').map(function(eachTag){
        return parseInt(eachTag);
    });

    var patient = new Patient({  
          name: req.params('patientName'),
          fatherName:   req.params('patientFatherName'),
          dob:new Date(req.params('patientDob')),
          bloadGroup : req.params('patientBloodGroup'),
          age:req.params('patientAge'),
          sex: req.params('patientSex'),
          nationality:req.params('patientNationality'),
          phone: req.params('patientPhone'),
          description: req.params('patientDesc'),
          specialization:Specilizationtag,
          attachmentId:attachemntTag});
    patient.save(function(err){
        if(err) {console.log("Error Occured"+err);};
    });
    res.end();
};