英文:
How to create a file with content and download it with THYMELEAF
问题
@PostMapping("/filegenerator")
public String createFile(@ModelAttribute("page") Page page, Model model) {
List<String> lines = new ArrayList<String>();
//某些代码 ..........
lines.forEach(l -> {
System.out.println(l);
});
//在这里我需要创建一个带有行列表的文件
//并且还需要添加一些代码来进行下载
return "filegenerator";
}
英文:
I'm working on a spring boot project with thymeleaf and I need to create a file and put some lines on it then send it for the user to download it.
@PostMapping("/filegenerator")
public String createFile(@ModelAttribute("page") Page page, Model model) {
List<String> lines = new ArrayList<String>();
//Some code ..........
lines.forEach(l->{
System.out.println(l);
});
//Here I need to create a file with the List of lines
//And also put some code to download it
return "filegenerator";
}
答案1
得分: 3
如果您想要返回一个文件，您可能希望将其以流的方式传输，以限制内存的使用量（或者至少这可能是Spring Framework创建者的推理）。在您的情况下，我理解该文件相当小，实际上不需要持久化存储在任何地方。这只是基于上传表单的一次性下载，对吗？
所以这种方法在我的电脑上有效：
@PostMapping("/filegenerator")
public void createFile(HttpServletResponse response) throws IOException {
List<String> lines = Arrays.asList("line1", "line2");
InputStream is = new ByteArrayInputStream(lines.stream().collect(Collectors.joining("\n")).getBytes());
IOUtils.copy(is, response.getOutputStream());
response.setContentType("application/sql");
response.setHeader("Content-Disposition", "attachment; filename=\"myquery.sql\"");
response.flushBuffer();
}
注意 content-disposition 标头。它明确表示您不希望在浏览器中显示文件，而是希望将其作为文件下载，myquery.sql 是将要下载的文件的名称。
英文:
So if you want to return a file, you probably want to stream it to limit the amount of memory used (or at least that was probably the reasoning of Spring Framework creators). In your case I understand that the file is fairly small and doesn't really have to be persisted anywhere. It's just a one time download based on the uploaded form, right?
so this approach worked on my PC:
@PostMapping("/filegenerator")
public void createFile(HttpServletResponse response) throws IOException {
List<String> lines = Arrays.asList("line1", "line2");
InputStream is = new ByteArrayInputStream(lines.stream().collect(Collectors.joining("\n")).getBytes());
IOUtils.copy(is, response.getOutputStream());
response.setContentType("application/sql");
response.setHeader("Content-Disposition", "attachment; filename=\"myquery.sql\"");
response.flushBuffer();
}
note the content-disposition header. It explicitly states that you don't want to display the file in the browser, but instead you want it to be downloaded as a file and myquery.sql is the name of that file that will be downloaded.
答案2
得分: 1
@Kamil janowski
现在的代码如下所示：
@PostMapping("/filegenerator")
public String createFile(@ModelAttribute("page") Page page, Model model, HttpServletResponse response) throws IOException {
List<String> lines = new ArrayList<String>();
if (!page.getTables().get(0).getName().equals("")) {
List<String> output = so.createTable(page.getTables());
output.forEach(line -> lines.add(line));
}
if (!page.getInserttables().get(0).getName().equals("")) {
List<String> output = so.insert(page.getInserttables());
output.forEach(line -> lines.add(line));
}
if (!page.getUpdatetables().get(0).getName().equals("")) {
List<String> output = so.update(page.getUpdatetables());
output.forEach(line -> lines.add(line));
}
lines.forEach(l -> {
System.out.println(l);
});
InputStream is = new ByteArrayInputStream(lines.stream().collect(Collectors.joining("\n")).getBytes());
IOUtils.copy(is, response.getOutputStream());
response.setContentType("application/sql");
response.setHeader("Content-Disposition", "attachment; filename=\"myquery.sql\"");
response.flushBuffer();
model.addAttribute("page", getPage());
return "filegenerator";
}
英文:
@Kamil janowski
This is how it looks like now
@PostMapping("/filegenerator")
public String createFile(@ModelAttribute("page") Page page, Model model,HttpServletResponse response) throws IOException{
List<String> lines = new ArrayList<String>();
if(page.getTables().get(0).getName()!="") {
List<String> output = so.createTable(page.getTables());
output.forEach(line -> lines.add(line));
}
if(page.getInserttables().get(0).getName()!="") {
List<String> output = so.insert(page.getInserttables());
output.forEach(line -> lines.add(line));
}
if(page.getUpdatetables().get(0).getName()!="") {
List<String> output = so.update(page.getUpdatetables());
output.forEach(line -> lines.add(line));
}
lines.forEach(l->{
System.out.println(l);
});
InputStream is = new ByteArrayInputStream(lines.stream().collect(Collectors.joining("\n")).getBytes());
IOUtils.copy(is, response.getOutputStream());
response.setContentType("application/sql");
response.setHeader("Content-Disposition", "attachment; filename=\"myquery.sql\"");
response.flushBuffer();
model.addAttribute("page", getPage());
return "filegenerator";
}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论