1
<html>
<head>
<title>JSP Form</title>
<style>
</style>
</head>
<body>
<form action="TestFileHandling.jsp" method="post">
<fieldset>
<legend>User Information</legend>
<label for="question">Question</label>
<input type="text" name="question" /> <br/>
<input type="submit" value="submit">
</fieldset>
</form>
</body>
</html>
以上是讓用戶在發送之前輸入問題的簡單表單。使用JSP的反饋表格
<%@page import="myPackage.FileReaderWriter"%>
<%@page import="java.util.Vector"%>
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<%
Vector<String[]> v = new Vector<String[]>();
String[] str1 = {request.getParameter("question")};
v.addElement(str1);
FileReaderWriter.saveVectorToFile(v, "MyTestFile.txt");
%>
<%
Vector<String[]> vec = FileReaderWriter.readFileToVector ("MyTestFile.txt");
for (int i = 0; i < vec.size(); i++)
{
out.print("|");
for (int j = 0; j < vec.elementAt(i).length; j++)
{
out.print(vec.elementAt(i)[j] + "|");
}
%>
<br>
<%
}
%>
</body>
</html>
這部分將輸入的問題保存到一個文本文件中，然後打開文件以顯示裏面的內容。
這一切是通過下面的Java代碼來完成：
package myPackage;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Vector;
public class FileReaderWriter {
public static void saveVectorToFile(Vector<String[]> v, String sFileName)
{
try
{
// Create a new file writer
FileWriter writer = new FileWriter(sFileName);
// Loop through all the elements of the vector
for (int i = 0; i < v.size(); i++)
{
// Capture the index of the last item of each array
int lastIndex = v.elementAt(i).length - 1;
// Loop through all the items of the array, except
// the last one.
for (int j = 0; j < lastIndex; j++)
{
// Append the item to the file.
writer.append(v.elementAt(i)[j]);
// Append a comma after each item.
writer.append(',');
}
// Append the last item.
writer.append(v.elementAt(i)[lastIndex]);
// Append a new line character to the end of the line
// (i.e. Start new line)
writer.append('\n');
}
// Save and close the file
writer.flush();
writer.close();
}
// Catch the exception if an Input/Output error occurs
catch (IOException e)
{
e.printStackTrace();
}
}
public static Vector<String[]> readFileToVector(String sFileName)
{
// Initialise the BufferedReader
BufferedReader br = null;
// Create a new Vector. The elements of this Vector are String arrays.
Vector<String[]> v = new Vector<String[]>();
try
{
// Try to read the file into the buffer
br = new BufferedReader(new FileReader(sFileName));
// Initialise a String to save the read line.
String line = null;
// Loop to read all the lines
while ((line = br.readLine()) != null)
{
// Convert the each line into an array of Strings using
// comma as a separator
String[] values = line.split(",");
// Add the String array into the Vector
v.addElement(values);
}
}
// Catch the exception if the file does not exist
catch (FileNotFoundException ex)
{
ex.printStackTrace();
}
// Catch the exception if an Input/Output error occurs
catch (IOException ex)
{
ex.printStackTrace();
}
// Close the buffer handler
finally
{
try
{
if (br != null)
br.close();
} catch (IOException ex)
{
ex.printStackTrace();
}
}
// return the Vector
return v;
}
}
我的問題是，雖然一切似乎是工作，每次我進入一個新的問題，舊的文本文件被覆蓋。有沒有一種方法可以解決這個問題，以便每次我在表單中輸入一個新問題時，它都會與所有其他問題一起添加到文本文件中，而不是不斷覆蓋文本文件？感謝您的任何信息或幫助。
強制性：你真的不應該使用小腳本的。 – millimoose 2012-02-14 22:12:43
+1關於scriptlets的評論，這是一個很好的鏈接http://stackoverflow.com/questions/3177733/how-to-avoid-java-code-in-jsp-files – reevesy 2012-02-14 22:21:16