PHP和HTML选择标签
[英]PHP and HTML select tag
问题描述
我已经开始使用PHP和HTML，并希望通过三个下拉列表（选择标记）执行简单的代码。 但是当我从其中一个进行选择时，其他两个选择的值就会消失。 提交值时应保存值，然后回显。 如果是，我该怎么办。 示例代码将不胜感激。
<?php // formtest_2.php
$name_vid = $name_type = $name_model = "";
if (isset($_POST['vid']))$name_vid=($_POST['vid']);
else $name_vid="no";
if (isset($_POST['type']))$name_type=sanitizeString($_POST['type']);
else $name_type="no";
if (isset($_POST['model']))$name_model=sanitizeString($_POST['model']);
else $name_model="no";
echo <<<_END
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="" selected>Product</option>
<option value = "apple">apple</option>
<option value = "cherry">cherry</option>
<option value = "orange">orange</option>
</select>
<input type="submit"/><br />
<select name="type" size="1">
<option value="" selected>Color</option>
<option value = "green">green</option>
<option value = "red">red</option>
<option value = "orange">orange</option>
</select>
<input type="submit"/><br />
<select name="model" size="1">
<option value="" selected>Model</option>
<option value = "1-a">1-a</option>
<option value = "2-b">2-b</option>
<option value = "3-c">3-c</option>
</select>
<input type="submit"/><br />
</form>
</body>
</html>
_END;
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>
2 个解决方案
解决方案1
1 2012-12-26 10:26:13
我认为您需要在提交后重新选择下拉菜单的值。 以下代码将解决。
<?php // formtest_2.php
$name_vid = $name_type = $name_model = "(nothing)";
if (isset($_POST['vid']) && $_POST['vid']) $name_vid=($_POST['vid']);
if (isset($_POST['type']) && $_POST['type']) $name_type=sanitizeString($_POST['type']);
if (isset($_POST['model']) && $_POST['model']) $name_model=sanitizeString($_POST['model']);
?>
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="">Product</option>
<option value = "apple" <?php if($name_vid == 'apple') echo 'selected="selected"'; ?>>apple</option>
<option value = "cherry" <?php if($name_vid == 'cherry') echo 'selected="selected"'; ?>>cherry</option>
<option value = "orange" <?php if($name_vid == 'orange') echo 'selected="selected"'; ?>>orange</option>
</select>
<br />
<select name="type" size="1">
<option value="">Color</option>
<option value = "green" <?php if($name_type == 'green') echo 'selected="selected"'; ?>>green</option>
<option value = "red" <?php if($name_type == 'red') echo 'selected="selected"'; ?>>red</option>
<option value = "orange" <?php if($name_type == 'orange') echo 'selected="selected"'; ?>>orange</option>
</select>
<br />
<select name="model" size="1">
<option value="">Model</option>
<option value = "1-a" <?php if($name_model == '1-a') echo 'selected="selected"'; ?>>1-a</option>
<option value = "2-b" <?php if($name_model == '2-b') echo 'selected="selected"'; ?>>2-b</option>
<option value = "3-c" <?php if($name_model == '3-c') echo 'selected="selected"'; ?>>3-c</option>
</select>
<input type="submit"/><br />
</form>
</body>
</html>
<?php
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>
我不会使用heredoc语法（“ <<<”）来打印HTML。
解决方案2
0 已采纳 2012-12-26 10:54:43
试试看，我做了一个提交按钮，并在提交后重新选择了值：
<?php
// formtest_2.php
$name_vid = $name_type = $name_model = "";
if (isset($_POST['vid']))
$name_vid = ($_POST['vid']);
else
$name_vid = "no";
if (isset($_POST['type']))
$name_type = sanitizeString($_POST['type']);
else
$name_type = "no";
if (isset($_POST['model']))
$name_model = sanitizeString($_POST['model']);
else
$name_model = "no";
///////////////////
if($name_vid == 'apple')
{
$v1 = 'selected';
}
elseif($name_vid == 'cherry')
{
$v2 = 'selected';
}
elseif($name_vid == 'orange')
{
$v3='selected';
}
////////////////////////
if($name_type == 'green')
{
$t1 = 'selected';
}
elseif($name_type == 'red')
{
$t2 = 'selected';
}
elseif($name_type == 'orange')
{
$t3='selected';
}
///////////////////////
if($name_model == '1-a')
{
$m1 = 'selected';
}
elseif($name_model == '2-b')
{
$m2 = 'selected';
}
elseif($name_model == '3-c')
{
$m3='selected';
}
?>
<html>
<head>
<title>Form Test Two</title>
</head>
<body>
Make your selection:
<form name="fruite_form" action="formtest_2.php" method="post">
<select name="vid" size="1">
<option value="" selected>Product</option>
<option <?=$v1?> value = "apple">apple</option>
<option <?=$v2?> value = "cherry">cherry</option>
<option <?=$v3?> value = "orange">orange</option>
</select>
<select name="type" size="1">
<option value="" selected>Color</option>
<option <?=$t1?> value = "green">green</option>
<option <?=$t2?>value = "red">red</option>
<option <?=$t3?>value = "orange">orange</option>
</select>
<select name="model" size="1">
<option value="" selected>Model</option>
<option <?=$m1?> value = "1-a">1-a</option>
<option <?=$m2?>value = "2-b">2-b</option>
<option <?=$m3?>value = "3-c">3-c</option>
</select>
<input name="submitButtom" id="submitButton" type="submit"/><br />
</form>
</body>
</html>
<?
echo "Your selection is: $name_vid and $name_type and $name_model";
function sanitizeString($var)
{
$var = stripslashes($var);
$var = htmlentities($var);
$var = strip_tags($var);
return $var;
}
?>
随意的顶部添加回您的提交按钮。 但是，给每个人一个唯一的名称，也不要忘记命名您的表单，作为一种好的做法，也请给一个ID，该ID与name属性相同。
更新：为了确保您确实得到了帖子，因为这是您的第一个问题，所以请在代码末尾打印
echo $_POST['vid'] . ' ' . $_POST['type'] . ' ' . $_POST['model'] . '<br/><br/>';
并查看post在提交后是否真正拥有该值，如果您从post那里获得了一个值，但没有从分配的变量中得到一个值，则检查顶部使用的条件来分配您的值。
//您需要检查post isset是否具有实际值，仅比应分配的变量要大。 就像西胡所说的那样。
PHP While-选择html标记
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