jQuery自动补全插件使用，三种获取数据源方式

浏览数：27 / 时间：2015年06月09日

jQuery有很多很多的已经实现，很漂亮的插件，autocomplete就是其中之一。jQuery ui autocomplete主要支持字符串Array、JSON两种数据格式。

主要参数：

Source:数据源，类型为String、Array、Function，其中String为ajax请求的服务器端地址，返回Array/JSON格式，Array即为数组，静态定义到页面中的数据，下面会有具体的 demo，

Function(request,response):通过request.term获得输入的值，response(Array)来呈现数据（JSONP是这种方式）；

minLength:当输入框内字符串长度达到minLength时，激活Autocomplete

autoFocus:当autocomplete选择菜单弹出时，自动选中第一个。

delay：即延迟多少毫秒autocomplete

disabled：是否禁用自动完成功能，默认false

jQuery ui提供的常用方法：

close():关闭智能提示框

destory():销毁智能提示框，将其所产生的元素完全删除，使其恢复至初始状态

disable():禁用自动完成功能

enable():开启自动完成功能

主要事件：

change(event,ul):当值改变时发生，ui.item为选中项

close(event,ui):当智能提示框关闭时发生

create(event,ui):当智能提示框创建时发生，可以在此事件中，对外观进行控制

focus(event,ui):当智能提示列表任意一项获得焦点时发生，ui.item为获得焦点的项

open(event,ui):当智能提示框打开或更新时发生

response(event,ui):在搜索完成之后智能提示框显示前发生，可以在此时间中对显示项进行处理

search(event,ui):在开始请求之前发生，可以在此事件中返回false来取消请求

select(event,ui):当智能提示框中任意一项被选中时发生，ui.item为选中项

使用时应首先需要导入相关的js文件。下载地址：http://jqueryui.com/autocomplete/

第一种获取数据源方式：String，即通过字符串发送ajax，本例为了省事，直接就使用了原始的servlet，没有用到框架，只是演示效果

dao 层

package com.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

public class Dao {

    private static Connection getConnection() throws Exception{
        Class.forName("com.mysql.jdbc.Driver");
        return DriverManager.getConnection("jdbc:mysql://localhost:3306/itac", "root", "root");
    }
    
    public static List<String> getNames(String username) throws Exception{
        Connection c = getConnection();
        Statement stat = c.createStatement();
        ResultSet rs = stat.executeQuery("select user_name from t_user where user_name like ‘%"+username+"%‘");
        List<String> strs = new ArrayList<String>();
        while(rs.next()){
            strs.add(rs.getString("user_name"));
        }
        return strs;
    }
}

servlet层

package com.servlet;

import java.io.IOException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.dao.Dao;
@WebServlet(name="autoServlet",value="/auto")
public class AutoServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
   
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=utf-8");//解决乱码
        String username = request.getParameter("term");//默认传过来的参数名成为term，封装了文本框中输入的值
        StringBuffer sb = new StringBuffer("[");
        try {
            List<String> names = Dao.getNames(username);
            for(int i=0;i<names.size();i++){
                if(i==names.size()-1){
                    //注意在拼接的时候，要用双引号，单引号我试过，不起作用好像是,至少key必须是双引号，最好都写成双引号
                    /*
                     * 其中label属性用于显示在autocomplete弹出菜单，而value属性则是选中后给文本框赋的值。如果没有指定其中一个属性
                     * 则用另一个属性替代(即value和label值一样)，如果label和value都没有指定，则无法用于autocomplete的提示。    
                     */
                    sb.append("{\"lable\":\""+names.get(i)+"\",\"value\":\""+names.get(i)+"\"}]");
                }else{
                    sb.append("{\"lable\":\""+names.get(i)+"\",\"value\":\""+names.get(i)+"\"},");
                }
            }
            System.out.println(sb.toString());
            response.getWriter().write(sb.toString());
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!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>
<link href="${pageContext.request.contextPath }/resources/css/jquery-ui.css" rel="stylesheet">
    <style>
    body{
        font: 62.5% "Trebuchet MS", sans-serif;
        margin: 50px;
    }
    </style>
<script src="${pageContext.request.contextPath }/resources/js/jquery.js"></script>
<script src="${pageContext.request.contextPath }/resources/js/jquery-ui.js"></script>
<%-- <script src="${pageContext.request.contextPath }/resources/js/jquery.ui.core.js"></script>
<script src="${pageContext.request.contextPath }/resources/js/jquery.ui.autocomplete.js"></script>
<script src="${pageContext.request.contextPath }/resources/js/jquery.ui.position.js"></script>
<script src="${pageContext.request.contextPath }/resources/js/jquery.ui.widget.js"></script> --%>
</head>
<body>
    <input id="username" type="text" value="" name="username"/>
</body>  
<script type="text/javascript">
//String方式
$(function(){
    $("#username").autocomplete({
        source:"<c:url value="/auto"/>",
        minLength:1        
    });
});

</script>
</html>

第二种获取数据源方式：回调函数

dao层

package com.dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import domain.User;

public class Dao2 {
    private static Connection getConnection() throws Exception{
        Class.forName("com.mysql.jdbc.Driver");
        return DriverManager.getConnection("jdbc:mysql://localhost:3306/itac", "root", "root");
    }
    
    public static List<User> getNames(String username) throws Exception{
        Connection c = getConnection();
        Statement stat = c.createStatement();
        ResultSet rs = stat.executeQuery("select * from t_user where user_name like ‘%"+username+"%‘");
        List<User> users = new ArrayList<User>();
        while(rs.next()){
            User u = new User();
            u.setUserId(Integer.parseInt(rs.getString("user_id")));
            u.setUserName(rs.getString("user_name"));
            u.setBirth(rs.getString("user_date"));
            users.add(u);
        }
        return users;
    }
}

User

package domain;

public class User {

    private Integer userId;
    private String userName;
    private String birth;
    
    //getter setter tostring
    
}

servlet层

package com.servlet;

import java.io.IOException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.dao.Dao2;
import com.google.gson.Gson;

import domain.User;

/**
 * Servlet implementation class AutoServlet2
 */
@WebServlet("/auto2")
public class AutoServlet2 extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
   
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }

    
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=utf-8");
        System.out.println(request.getParameter("userName"));
        try {
            List<User> users = Dao2.getNames(request.getParameter("userName"));
            Gson gson = new Gson();
            String str = gson.toJson(users);
            response.getWriter().write(str);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!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>
<link href="${pageContext.request.contextPath }/resources/css/jquery-ui.css" rel="stylesheet">
    <style>
    body{
        font: 62.5% "Trebuchet MS", sans-serif;
        margin: 50px;
    }
    </style>
<script src="${pageContext.request.contextPath }/resources/js/jquery.js"></script>
<script src="${pageContext.request.contextPath }/resources/js/jquery-ui.js"></script>
</head>
<body>
<input type="text" name="userName" id="userName"/>
</body>
<script type="text/javascript">
$("#userName").autocomplete({
source: function( request, response ) {
    $.ajax({
        type:"post",
        url: "<c:url value="/auto2"/>",
        dataType: "json",
        data:{
            userName: request.term
        },
        success: function( data ) {
            response( $.map( data, function( item ) {
                return {   //lable为下拉列表显示数据源。value为选中放入到文本框的值，这种方式可以自定义显示
                    lable:item.userName,    
                    value: item.userName
                }
            }));
        }
    });
},
minLength: 1,
select: function( event, ui ) { //移动键盘上下键，自动将下拉列表的数据放入到文本框，不过不写这个配置也是可以的，默认就行，具体这个还不知道是做什么
    $("#userName").val(ui.item.userName);
}
});
</script>
</html>

第三种方式较简单，直接在页面上放入，比如：

// 本地json数组
var availableTagsJSON = [
{ label: "C# Language", value: "C#" },
{ label: "C++ Language", value: "C++" },
{ label: "Java Language", value: "Java" },
{ label: "JavaScript Language", value: "JavaScript" },
{ label: "ASP.NET", value: "ASP.NET" },
{ label: "JSP", value: "JSP" },
{ label: "PHP", value: "PHP" },
{ label: "Python", value: "Python" },
{ label: "Ruby", value: "Ruby" }
];
$("#local").autocomplete({
source: availableTagsJSON
});