Question

  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws     ServletException, IOException {
    // TODO Auto-generated method stub

    try {
        PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("/home/ahis/Desktop/outfilename.txt", true)));
        out.println("the text");
        out.close();
    } catch (IOException e) {

    }

我有上面的代码用于将文本写入文件。我需要从文件中获取此数据，并需要将此值设置为文本框的内容。

我有以下jsp文件。

         <%@ page language="java" contentType="text/html; charset=UTF-8"
      pageEncoding="UTF-8"%>
   <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"    "http://www.w3.org    /TR/html4/loose.dtd">
 <html>
 <head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form method="GET" action='Controller' name="good">
<input type="submit" name="submit" value="submit">
<input type="text" name="done"> 
</form>
</body>

Answer 1

将此代码添加到servlet中用于访问文件

中的数据

 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws     ServletException, IOException {
    // TODO Auto-generated method stub

String TextValue=null;
try {
         File file = new File(fileName);
         Scanner scanner = new Scanner(file);
         while (scanner.hasNextLine()) {
           if(TextValue==null)
          {
           TextValue=scanner.nextLine();
          }
          else
        {
           TextValue=TextValue + " "+scanner.nextLine();

        }
}
             scanner.close();
           } catch (FileNotFoundException e) {
             e.printStackTrace();
           }

request.setAttribute("TextValue",TextValue);

}

JSP文件中的更改是

<form method="GET" action='Controller' name="good">
<input type="submit" name="submit" value="submit"/>
<input type="text" name="done" value='<%=request.getAttribute("TextValue")%>'/> 
</form>

希望这会对你有所帮助。

如何使用servlet在文本框中设置值

1 个答案: