利用js和Ajax實現的表單的檢查和提交
阿新 • • 發佈:2019-02-19
checkUser.java
package demo; import java.io.IOException; import java.io.PrintWriter; import java.util.Arrays; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class checkUser extends HttpServlet { public checkUser() { super(); } public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setCharacterEncoding("utf-8"); List<String> userNames = Arrays.asList("AAA","BBB","CCC");//假設這幾個使用者名稱已被使用 String username = request.getParameter("username"); PrintWriter out = response.getWriter(); if(userNames.contains(username)){ //返回標誌判斷使用者名稱是否存在 out.print("yes"); //該使用者名稱已存在 } else{ out.print("no"); //該使用者名稱不存在 } } public void init() throws ServletException { // Put your code here } }