0

我正在创建 3 个基于彼此选择的下拉列表，因此第一个选择是正常的，但第二个取决于第一个选择，第三个取决于第二个选择这是表格结构

类别子类别和子子类别

这是代码

<?php

require "config.php"; //  Database details 
?>

<!doctype html public "-//w3c//dtd html 3.2//en">

<html>

<head>
<title>Demo of Three Multiple drop down list box from plus2net</title>
<meta name="GENERATOR" content="Arachnophilia 4.0">
<meta name="FORMATTER" content="Arachnophilia 4.0">
<SCRIPT language=JavaScript>
function reload(form)
{
var val=form.cat.options[form.cat.options.selectedIndex].value; 
self.location='dd3.php?cat=' + val ;
}
function reload3(form)
{
var val=form.cat.options[form.cat.options.selectedIndex].value; 
var val2=form.subcat.options[form.subcat.options.selectedIndex].value; 

self.location='dd3.php?cat=' + val + '&cat3=' + val2 ;
}

</script>
</head>

<body>
<?



$quer2=mysql_query("SELECT DISTINCT category,cat_id FROM category order by category"); 

$cat=$_GET['cat']; 
if(isset($cat) and strlen($cat) > 0){
$quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory where cat_id=$cat order by subcategory"); 
}else{$quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory order by subcategory"); } 




$cat3=$_GET['cat3'];
if(isset($cat3) and strlen($cat3) > 0){
$quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 where subcat_id=$cat3 order by subcat2"); 
}else{$quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 order by subcat2"); } 


echo "<form method=post name=f1 action='dd3ck.php'>";

echo "<select name='cat' onchange=\"reload(this.form)\"><option value=''>Select one</option>";
while($noticia2 = mysql_fetch_array($quer2)) { 
if($noticia2['cat_id']==@$cat){echo "<option selected value='$noticia2[cat_id]'>$noticia2[category]</option>"."<BR>";}
else{echo  "<option value='$noticia2[cat_id]'>$noticia2[category]</option>";}
}
echo "</select>";

echo "<select name='subcat' onchange=\"reload3(this.form)\"><option value=''>Select one</option>";
while($noticia = mysql_fetch_array($quer)) { 
if($noticia['subcat_id']==@$cat3){echo "<option selected value='$noticia[subcat_id]'>$noticia[subcategory]</option>"."<BR>";}
else{echo  "<option value='$noticia[subcat_id]'>$noticia[subcategory]</option>";}
}
echo "</select>";

echo "<select name='subcat3' ><option value=''>Select one</option>";
while($noticia = mysql_fetch_array($quer3)) { 
echo  "<option value='$noticia[subcat2]'>$noticia[subcat2]</option>";
}
echo "</select>";



echo "<input type=submit value='Submit the form data'></form>";
?>

</body>

</html>

谁能帮我 ？？

这是我运行此代码时的输出

0){ $quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory where cat_id=$cat order by subcategory"); }else{$quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory order by subcategory"); } $cat3=$_GET['cat3']; if(isset($cat3) and strlen($cat3) > 0){ $quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 where subcat_id=$cat3 order by subcat2"); }else{$quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 order by subcat2"); } echo "
"; echo ""; echo ""; echo ""; echo "
"; ?>
4

2 回答 2

0

在较低的 php 代码的开头只有一个<?not a ，我认为 if 语句中的 > 结束了它。<?php但这可能不是问题。

于 2013-04-21T18:12:06.113 回答
0

可能是您的服务器中禁用了 PHP 短标签。因此，如果您对 PHP 使用短标签，它将无法正常工作。

检查此链接以了解如何在 PHP 中启用短标签。http://www.tomjepson.co.uk/enabling-short-tags-in-php/

但是如果你不能启用短标签，那么你需要正确打开PHP标签

<?应该是错的<?php。在您的代码中更改它。完整的代码将是：

<?php

require "config.php"; //  Database details 
?>

<!doctype html public "-//w3c//dtd html 3.2//en">

<html>

<head>
<title>Demo of Three Multiple drop down list box from plus2net</title>
<meta name="GENERATOR" content="Arachnophilia 4.0">
<meta name="FORMATTER" content="Arachnophilia 4.0">
<SCRIPT language=JavaScript>
function reload(form)
{
var val=form.cat.options[form.cat.options.selectedIndex].value; 
self.location='dd3.php?cat=' + val ;
}
function reload3(form)
{
var val=form.cat.options[form.cat.options.selectedIndex].value; 
var val2=form.subcat.options[form.subcat.options.selectedIndex].value; 

self.location='dd3.php?cat=' + val + '&cat3=' + val2 ;
}

</script>
</head>

<body>
<?php



$quer2=mysql_query("SELECT DISTINCT category,cat_id FROM category order by category"); 

$cat=$_GET['cat']; 
if(isset($cat) and strlen($cat) > 0){
$quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory where cat_id=$cat order by subcategory"); 
}else{$quer=mysql_query("SELECT DISTINCT subcategory,subcat_id FROM subcategory order by subcategory"); } 




$cat3=$_GET['cat3'];
if(isset($cat3) and strlen($cat3) > 0){
$quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 where subcat_id=$cat3 order by subcat2"); 
}else{$quer3=mysql_query("SELECT DISTINCT subcat2 FROM subcategory2 order by subcat2"); } 


echo "<form method=post name=f1 action='dd3ck.php'>";

echo "<select name='cat' onchange=\"reload(this.form)\"><option value=''>Select one</option>";
while($noticia2 = mysql_fetch_array($quer2)) { 
if($noticia2['cat_id']==@$cat){echo "<option selected value='$noticia2[cat_id]'>$noticia2[category]</option>"."<BR>";}
else{echo  "<option value='$noticia2[cat_id]'>$noticia2[category]</option>";}
}
echo "</select>";

echo "<select name='subcat' onchange=\"reload3(this.form)\"><option value=''>Select one</option>";
while($noticia = mysql_fetch_array($quer)) { 
if($noticia['subcat_id']==@$cat3){echo "<option selected value='$noticia[subcat_id]'>$noticia[subcategory]</option>"."<BR>";}
else{echo  "<option value='$noticia[subcat_id]'>$noticia[subcategory]</option>";}
}
echo "</select>";

echo "<select name='subcat3' ><option value=''>Select one</option>";
while($noticia = mysql_fetch_array($quer3)) { 
echo  "<option value='$noticia[subcat2]'>$noticia[subcat2]</option>";
}
echo "</select>";



echo "<input type=submit value='Submit the form data'></form>";
?>

</body>

</html>
于 2013-04-21T18:12:30.480 回答