Home > Article > Web Front-end > How to implement the three-level linkage menu bar of ajax
This time I will show you how to implement ajax's three-level linkage menu bar. What are the precautions for the implementation of ajax's three-level linkage menu bar? The following is a practical case, let's take a look.
The example in this article shares the specific code for ajax three-level linkage display for your reference. The specific content is as follows
1. test.php
<script src="../jquery-1.11.2.min.js"></script> <script src="sanji.js"></script> <title>无标题文档</title> </head> <body> <h1>三级联动</h1> <p id="sanji"></p> </body> </html>
2. sanji.js
// JavaScript Document
$(document).ready(function(e) {
//找到ID=SANJI的p，造三个下拉扔进去
$("#sanji").html("<select id='sheng'></select><select id='shi'></select><select id='qu'></select>");
//加载省的数据
LoadSheng();
//加载市的数据
LoadShi();
//加载区的数据
LoadQu();
//给省的下拉加点击事件
$("#sheng").click(function(){
//重新加载市
LoadShi();
//重新加载区
LoadQu();
})
//给市的下拉加点击事件
$("#shi").click(function(){
//重新加载区
LoadQu();
})
});
//加载省份的方法
function LoadSheng()
{
//省的父级代号
var pcode = "0001";
$.ajax({
async:false,
url:"chuli.php",
data:{pcode:pcode},
type:"POST",
dataType:"TEXT",
success: function(data){
var hang = data.trim().split("|");
var str = "";
for(var i=0;i<hang.length;i++)
{
var lie = hang[i].split("^");
str = str+"<option value='"+lie[0]+"'>"+lie[1]+"</option>";
}
$("#sheng").html(str);
}
});
}
//加载市的方法
function LoadShi()
{
//找市的父级代号
var pcode = $("#sheng").val();
$.ajax({
async:false,
url:"chuli.php",
data:{pcode:pcode},
type:"POST",
dataType:"TEXT",
success: function(data){
var hang = data.trim().split("|");
var str = "";
for(var i=0;i<hang.length;i++)
{
var lie = hang[i].split("^");
str = str+"<option value='"+lie[0]+"'>"+lie[1]+"</option>";
}
$("#shi").html(str);
}
});
}
//加载区的方法
function LoadQu()
{
//找区的父级代号
var pcode = $("#shi").val();
$.ajax({
url:"chuli.php",
data:{pcode:pcode},
type:"POST",
dataType:"TEXT",
success: function(data){
var hang = data.trim().split("|");
var str = "";
for(var i=0;i<hang.length;i++)
{
var lie = hang[i].split("^");
str = str+"<option value='"+lie[0]+"'>"+lie[1]+"</option>";
}
$("#qu").html(str);
}
});
}
3. chuli.php
<?php
//给一个父级代号，返回该父级代号下所有的子地区
require "DBDA.class.php";
$db=new DBDA();
$pcode=$_POST["pcode"];
$sql="select areacode,areaname from chinastates where parentareacode='{$pcode}'";
echo $db->StrQuery($sql);
The method in the referenced encapsulation class that returns string
<?php
class DBDA
{
public $host = "localhost";
public $uid = "root";
public $pwd = "123";
public $dbname = "test_123";
//执行SQL语句返回相应的结果
//$sql 要执行的SQL语句
//$type 代表SQL语句的类型，0代表增删改，1代表查询
function query($sql,$type=0)
{
$db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname);
$result = $db->query($sql);
if($type)
{
//如果是查询，显示数据
return $result->fetch_all();
}
else
{
//如果是增删改，返回true或者false
return $result;
}
}
//返回字符串的方法
public function strquery($sql,$type=1)
{
$db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname);
$result = $db->query($sql);
$arr = $result->fetch_all();
$str="";
foreach($arr as $v)
{
$str = $str.implode("^",$v)."|";
}
$str = substr($str,0,strlen($str)-1);
return $str;
}
//返回JSON
function JSONQuery($sql,$type=1)
{
$db = new MySQLi($this->host,$this->uid,$this->pwd,$this->dbname);
$r = $db->query($sql);
if($type==1)
{
return json_encode($r->fetch_all(MYSQLI_ASSOC));
}
else
{
return $r;
}
}
}
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
Recommended reading:
How to make the browser remember ajax requests and control the browser to move forward and backward
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The above is the detailed content of How to implement the three-level linkage menu bar of ajax. For more information, please follow other related articles on the PHP Chinese website!