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PHP implements three-level cascading drop-down box, multi-select drop-down box, drop-down box plug-in, drop-down box code
PHP implements three-level cascading drop-down box, multi-select drop-down box, drop-down box plug-in, drop-down box code
This is the information I found on the Internet about implementing three-level cascading drop-down boxes in PHP. I would like to share it with you so that everyone can make progress together. The specific content is as follows
index.php:
<html>
<head>
<meta http-equiv="Content-Type" c type="text/javascript" src="aa.js"></script>
</head>
<body>
<form>
<label>
<select name="sel" . mysql_error());
if($result) while ($arr = mysql_fetch_array($result)){
echo <<<EOD
<option value={$arr["id"]}>{$arr["name"]}</option>
EOD; }
mysql_close($conn);
?>
</select>
</label>
<label>
<select name="sel2" >
<option>三级分类</option>
</select>
</label>
</form>
<input type=button value="send value" ><pre class="brush:php;toolbar:false"><!--
var xmlHttp
var xmlHttp2
//函数showMenu(str) - 功能函数1
function showMenu(str) xmlHttp=GetXmlHttpObject() //调用GetXmlHttpObject()函数，创建XMLHttpRequest对象
if (xmlHttp==null) //如果创建失败，则 alert ("Browser does not support HTTP Request")
return
var url="get2.php" //定义url , 其主要读取数据库
url=url+"?q="+str
url=url+"&sid="+Math.random() //Math对象的random方法，取随机数
xmlHttp. //设置当XMLHttpRequest对象xmlHttp状态改变时调用的函数,注意函数名后不要添加小括号
xmlHttp.open("GET",url,true) //使用XMLHttpRequest对象的open()方法 , 创建HTTP请求
xmlHttp.send(null) //使用XMLHttpRequest对象的open()方法 , 发送HTTP请求
}
//函数showMenu(str) - 功能函数1
function showMenu2(str)
{
xmlHttp2=GetXmlHttpObject() //调用GetXmlHttpObject()函数，创建XMLHttpRequest对象
if (xmlHttp2==null) //如果创建失败，则 alert ("Browser does not support HTTP Request")
return
var url="get2.php" //定义url , 其主要读取数据库
url=url+"?q2="+str
url=url+"&sid="+Math.random() //Math对象的random方法，取随机数
xmlHttp2.2 //设置当XMLHttpRequest对象xmlHttp状态改变时调用的函数,注意函数名后不要添加小括号
xmlHttp2.open("GET",url,true) //使用XMLHttpRequest对象的open()方法 , 创建HTTP请求
xmlHttp2.send(null) //使用XMLHttpRequest对象的open()方法 , 发送HTTP请求
}
//函数BuildSel() , 根据返回的的字串 , 重新构建新的下拉菜单控件Select - 功能函数2
function BuildSel(str,sel) //先清空原来的数据.
sel.options.length=0; var arrstr = new Array(); arrstr = str.split(",");
if(str.length>0) //循环
for(var i=0;i<arrstr.length;i++) var subarrstr=new Array(); subarrstr=arrstr[i].split("|");
sel.options.add(new Option(subarrstr[1],subarrstr[0])); sel.options[0].selected=true; }
//函数stateChanged() - 响应HTTP请求状态变化
function stateChanged() //判断XMLHttpRequest对象的readyState属性值是否为4,如果为4表示异步调用完成(注意:异步调用完成 不代表 异步调用成功)
if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete") //如果异步调用成功 --> XMLHttpRequest对象的status属性值为200 , html文件在本地运行,则xmlHttp.status的返回值为0,故应该加上xmlHttp.status==0
if(xmlHttp.status==200 || xmlHttp.status==0) //调用文档对象模型DOM的getElementById()方法查找html文件中的标签txtHint ,
//innerHTML为IE浏览器中的属性,可以用来更改标签间文本的内容 ,
//xmlHttp.responseText , 通过XMLHttpRequest的responseText属性来获取数据 responseText,结果为字符串;responseXML,结果为XML形式
// document.getElementByIdx_x_xx_x_xx("txtHint").innerHTML=xmlHttp.responseText
BuildSel(xmlHttp.responseText,document.getElementsByTagName_r("*").sel2)
showMenu2(document.getElementsByTagName_r("*").sel2.value); }
}
//函数stateChanged() - 响应HTTP请求状态变化
function stateChanged2() //判断XMLHttpRequest对象的readyState属性值是否为4,如果为4表示异步调用完成(注意:异步调用完成 不代表 异步调用成功)
if (xmlHttp2.readyState==4 || xmlHttp2.readyState=="complete") //如果异步调用成功 --> XMLHttpRequest对象的status属性值为200 , html文件在本地运行,则xmlHttp.status的返回值为0,故应该加上xmlHttp.status==0
if(xmlHttp2.status==200 || xmlHttp2.status==0) //调用文档对象模型DOM的getElementById()方法查找html文件中的标签txtHint ,
//innerHTML为IE浏览器中的属性,可以用来更改标签间文本的内容 ,
//xmlHttp.responseText , 通过XMLHttpRequest的responseText属性来获取数据 responseText,结果为字符串;responseXML,结果为XML形式
// document.getElementByIdx_x_xx_x_xx("txtHint").innerHTML=xmlHttp.responseText
BuildSel(xmlHttp2.responseText,document.getElementsByTagName_r("*").sel3) }
}
//函数GetXmlHttpObject() - 创建XMLHttpRequest对象,即创建一个异步调用对象
function GetXmlHttpObject() var xmlHttp=null;
try // Firefox, Opera 8.0+, Safari
xmlHttp=new XMLHttpRequest(); catch (e) //Internet Explorer
try xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); catch (e) xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); }
return xmlHttp; -->get2.php
<?php header('Content-Type:text/html;charset=GB2312'); $conn = mysql_connect('localhost', 'root', '') or die('Could not connect: ' . mysql_error());
mysql_select_db('fitment', $conn) or die ('Can\'t use database : ' . mysql_error());
mysql_query("set names 'gb2312'");
//如果传递过来q
if($_GET["q"]){
$strs = "SELECT * FROM fitment_sort WHERE supid=' ".$_GET["q"]."' ";
//echo $str;
$results = mysql_query($strs) or die("Invalid query: " . mysql_error());
if($results) while ($arrs = mysql_fetch_array($results)){
$strings .= $arrs["id"]."|".$arrs["name"].","; }
echo substr($strings,0,strlen($strings)-1); }
//如果传递过来q2
if($_GET["q2"]){
$str = "SELECT * FROM fitment_sort WHERE supid= '".$_GET["q2"]."'";
//echo $str;
$result = mysql_query($str) or die("Invalid query: " . mysql_error());
if($result) while ($arr = mysql_fetch_array($result)){
$string .= $arr["id"]."|".$arr["name"].","; } echo substr($string,0,strlen($string)-1); }
mysql_close($conn);
?>The above is the relevant code for implementing three-level cascading drop-down boxes in PHP. I hope it will be helpful for everyone to learn PHP programming.
The above introduces the implementation of three-level cascading drop-down boxes in PHP, including the contents of PHP and drop-down boxes. I hope it will be helpful to friends who are interested in PHP tutorials.
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