如何从Spring Controller中返回浏览器中的CSV数据
假设我在字符串中有CSV数据，并希望从Spring控制器返回它。 想象一下，数据看起来像这样
a,b,c 1,2,3 4,5,6 无论我尝试过什么，新行在响应内容中都是’\ n’，如果我在“\ n”中双重转义它们，响应只包含双反斜杠。 一般来说，如何在没有修改换行符的情况下返回带有换行符的纯文本数据？ 我知道如何返回纯文本，但仍然，内容带有转义的换行符……这就是我目前所拥有的（使用Spring 3.0.5，而不是选择）
@RequestMapping(value = "/api/foo.csv") public ResponseEntity fooAsCSV() { HttpHeaders responseHeaders = new HttpHeaders(); responseHeaders.add("Content-Type", "text/plain; charset=utf-8"); String data = "a,b,c\n1,2,3\n3,4,5"; return new ResponseEntity(data, responseHeaders, HttpStatus.OK); }
从字面上产生字符串
"a,b,c\n1,2,3\n,3,4,5"
在浏览器中。 如上所示，如何使用新线路生成正确的数据？
您可以使用例如直接写入响应
@RequestMapping(value = "/api/foo.csv") public void fooAsCSV(HttpServletResponse response) { response.setContentType("text/plain; charset=utf-8"); response.getWriter().print("a,b,c\n1,2,3\n3,4,5"); }
由于返回类型为void并且HttpServletResponse被声明为方法参数，因此假定在此方法返回时完成请求。
你在控制器方法上试过@ResponseBody吗？
@RequestMapping(value = "/api/foo.csv") @ResponseBody public String fooAsCSV(HttpServletResponse response) { response.setContentType("text/plain; charset=utf-8"); String data = "a,b,c\n1,2,3\n3,4,5"; return data; }
编辑：Spring文档在这里解释： http ： //docs.spring.io/spring/docs/3.0.x/spring-framework-reference/html/mvc.html#mvc-ann-responsebody
您可以使用库supercsv 。
net.sf.supercsv super-csv 2.1.0
以下是如何使用它：
1-定义要作为csv编写的模型类：
public class Book { private String title; private String description; private String author; private String publisher; private String isbn; private String publishedDate; private float price; public Book() { } public Book(String title, String description, String author, String publisher, String isbn, String publishedDate, float price) { this.title = title; this.description = description; this.author = author; this.publisher = publisher; this.isbn = isbn; this.publishedDate = publishedDate; this.price = price; } // getters and setters... }
2-做以下魔术：
import java.io.IOException; import java.util.Arrays; import java.util.List; import javax.servlet.http.HttpServletResponse; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.supercsv.io.CsvBeanWriter; import org.supercsv.io.ICsvBeanWriter; import org.supercsv.prefs.CsvPreference; /** * This Spring controller class implements a CSV file download functionality. * */ @Controller public class CSVFileDownloadController { @RequestMapping(value = "/downloadCSV") public void downloadCSV(HttpServletResponse response) throws IOException { String csvFileName = "books.csv"; response.setContentType("text/csv"); // creates mock data String headerKey = "Content-Disposition"; String headerValue = String.format("attachment; filename=\"%s\"", csvFileName); response.setHeader(headerKey, headerValue); Book book1 = new Book("Effective Java", "Java Best Practices", "Joshua Bloch", "Addision-Wesley", "0321356683", "05/08/2008", 38); Book book2 = new Book("Head First Java", "Java for Beginners", "Kathy Sierra & Bert Bates", "O'Reilly Media", "0321356683", "02/09/2005", 30); Book book3 = new Book("Thinking in Java", "Java Core In-depth", "Bruce Eckel", "Prentice Hall", "0131872486", "02/26/2006", 45); Book book4 = new Book("Java Generics and Collections", "Comprehensive guide to generics and collections", "Naftalin & Philip Wadler", "O'Reilly Media", "0596527756", "10/24/2006", 27); List listBooks = Arrays.asList(book1, book2, book3, book4); // uses the Super CSV API to generate CSV data from the model data ICsvBeanWriter csvWriter = new CsvBeanWriter(response.getWriter(), CsvPreference.STANDARD_PREFERENCE); String[] header = { "Title", "Description", "Author", "Publisher", "isbn", "PublishedDate", "Price" }; csvWriter.writeHeader(header); for (Book aBook : listBooks) { csvWriter.write(aBook, header); } csvWriter.close(); } }