javascript之使用ajax以mvc模式通过 Controller 发送数据

我正在尝试使用 knockout 将数据从我的 UI 发送到 Controller 。这是用于发送我的 ajax 请求 (PUT) 的 javascript

var model = new Object(); 
model.StudentID = ""; 
model.ActiveProgram = ""; 
model.ProgramDesc = self.programData(); 
model.Cohorts = self.associationData(); 
model.LoadIntent = self.loadIntentData(); 
model.Francophone = self.frenchData(); 
model.Gender = self.genderData(); 
 
    $.ajax({ 
        url: putStudentRegRequirementsUrl, 
        type: "PUT", 
        contentType: jsonContentType, 
        dataType: "json", 
        data: JSON.stringify(model), 
        //jsonData:model, 
        success: function (data) { 
            $('#notificationHost').notificationCenter('addNotification', { message: "Updated.", type: "info" }); 
        }, 
        error: function (jqXHR, textStatus, errorThrown) { 
            if (jqXHR.status != 0) 
            { 
                $('#notificationHost').notificationCenter('addNotification', { message: "Unable to update registration requirement.", type: "error"}); 
            } 
        } 
    }); 

但是当我调试它以查看我的 Controller 时，输入的字符串是空白的。这是我的 Controller

 [HttpPut] 
    public async Task<JsonResult> UpdateRegistrationRequirementAsync(string regRequirementJson) 
    { 
        try 
        { 
            var regRequirementModel = JsonConvert.DeserializeObject<RegistrationRequirement>(regRequirementJson); 
            var response = await ServiceClient.L09PutRegistrationRequirementAsync(CurrentUser.PersonId, regRequirementModel); 
            return Json(response); 
        } 
        catch( Exception ex) 
        { 
            Logger.Debug(ex, "Error updating Registration Requirement for user failed."); 
            Response.StatusCode = (int)HttpStatusCode.BadRequest; 
            return Json("Error updating Registration Requirement."); 
        }        
    } 

请您参考如下方法:

Action 将根据名称解析来自客户端的参数，因此您需要传递名称为 regRequirementJson 的参数，其中包含您的 json。所以改变这一行

data: JSON.stringify(model) 

到

data: { regRequirementJson: JSON.stringify(model) } 

并删除 contentType: jsonContentType。

或者您可以尝试其他方式。由于 ASP.NET 可以自行反序列化 json，因此您可以保持 js 代码不变并将 Controller 更新为

[HttpPut] 
public async Task<JsonResult> UpdateRegistrationRequirementAsync(RegistrationRequirement regRequirementModel ) 
{ 
    try 
    { 
        var response = await ServiceClient.L09PutRegistrationRequirementAsync(CurrentUser.PersonId, regRequirementModel); 
        return Json(response); 
    } 
    catch( Exception ex) 
    { 
        Logger.Debug(ex, "Error updating Registration Requirement for user failed."); 
        Response.StatusCode = (int)HttpStatusCode.BadRequest; 
        return Json("Error updating Registration Requirement."); 
    }