首页 > 解决方案 > Spring MVC - 有条件地返回 html 内容或模板内容

问题描述

当支付交易成功完成时,我想返回 HTML 内容(由外部服务提供)。

如果付款交易失败,我想返回付款表格(这是一个百里香模板)。

如何实现这种条件行为?

@PostMapping(value =  "/payment3ds/{offerId}/{company}")
public String payment3dsPost(
                             @PathVariable(value = "offerId") String offerId,
                             @PathVariable(value="company") String companyName,
                             @ModelAttribute("startSubscriptionRequest") StartSubscriptionRequest formInput, Model model) {

    try {
        String htmlContent = endpointsNoAuth.startSubscription3ds(formInput);

        return htmlContent; // value: "<html><body>...</body><html>
    } catch (IllegalArgumentException e) {
        Offer plan = subscriptionPlanRepo.findOneByIdAndCompanyName(Long.valueOf(offerId), companyName);
        model.addAttribute("subscriptionPlan", plan);
        model.addAttribute("errorText", e.getMessage());

        return "payment3ds"; // thymeleaf template
    }
}

标签: springspring-mvcthymeleaf

解决方案


为了解决这个问题,我首先开发了一个 View 接口的新实现。此实现将用于向客户端返回 HTML 代码:

public class HtmlView implements View {
    private String src;

    public HtmlView(String htmlContent) {
        this.src = htmlContent;
    }

    @Override
    public String getContentType() {
        return MediaType.TEXT_HTML_VALUE;
    }

    @Override
    public void render(Map<String, ?> map, HttpServletRequest httpServletRequest, HttpServletResponse response) throws Exception {
        response.setContentType(getContentType());
        response.getWriter().append(src);
    }
}

然后我更新了我的控制器以返回 ModelAndView:

@PostMapping(value =  "/payment3ds/{offerId}/{company}")
public ModelAndView payment3dsPost(...) {

    try {
        String htmlContent = "<html></html>";
        View view = new HtmlView(htmlContent);
        modelAndView.setView(view);

        return modelAndView;
    } catch (IllegalArgumentException e) {
        Offer plan = subscriptionPlanRepo.findOneByIdAndCompanyName(Long.valueOf(offerId), companyName);
        Company company = companyRepo.findByName(companyName);

        // Add your data in model
        Map<String, Object> model = modelAndView.getModel();

        modelAndView.setViewName("payment3ds"); // thymeleaf template
        return modelAndView; 
    }
}

如果我想返回 HTML 代码,我使用 HtmlView,否则我使用 ModelAndView 对象中的模板名称。


推荐阅读