Question

我目前正在使用一个可靠的下拉菜单，该菜单在jQuery和PHP的帮助下运行。正在提取MySQL数据库的值。是否有PHP回应可靠的下拉菜单的选定值？

HTML / PHP

<form action="" method="post">

        <select name="gender" id="gender" class="update">
            <option value="">Select one</option>
            <?php if (!empty($list)) { ?>
                <?php foreach($list as $row) { ?>
                    <option value="<?php echo $row['id']; ?>">
                        <?php echo $row['name']; ?>
                    </option>
                <?php } ?>
            <?php } ?>
        </select>

        <select name="category" id="category" class="update"
            disabled="disabled">
            <option value="">----</option>
        </select>

        <select name="colour" id="colour" class="update"
            disabled="disabled">
            <option value="">----</option>
        </select>

</form>

Answer 1

请添加jquery.js。你的HTML代码

    <select name="gender" id="gender" class="update">
        <option value="">Select one</option>
        <?php if (!empty($list)) { ?>
            <?php foreach($list as $row) { ?>
                <option value="<?php echo $row['id']; ?>">
                    <?php echo $row['name']; ?>
                </option>
            <?php } ?>
        <?php } ?>
    </select>

    <select name="category" id="category" class="update" disabled="disabled">
        <option value="">----</option>
    </select>

    <select name="colour" id="colour" class="update" disabled="disabled">
        <option value="">----</option>
    </select>
        //jquery code for source list
    <script type="text/javascript">
        $(document).ready(function(){
            $('#gender').change(function() {
              if ($(this).val()!='') {
                $("#category").load("postfile.php",{gender_id: $(this).val()});
                $("#category").removeAttr('disabled');
              }
            });
            //code on change of sel_source
            $('#category').change(function() {
              if ($(this).val()!='') {
                $("#colour").load("postfile.php",{category_id: $(this).val()});
                $("#colour").removeAttr('disabled');
              }

            });
        });
    </script> 



//postfile.php
//your mysql connection other things goes here
//code for category
$objDb = new PDO('mysql:host=localhost;dbname=dbname', 'ur_username', 'ur_password');
if(isset($_REQUEST['gender_id']) && !empty($_REQUEST['gender_id'])) {

           $sql = "SELECT * FROM `categories` WHERE `master` = ?";
    $statement = $objDb->prepare($sql);
    $statement->execute(array($_REQUEST['gender_id']));
    $list = $statement->fetchAll(PDO::FETCH_ASSOC);

    if(!empty($list)) {
        $output = '<option value="">Select</option>';
        foreach($list as $row) {              
                $output .= '<option value="'.$row['id'].'">'.$row['name'].'</option>';
        }
    } else {
        $output = '<option value="">Select</option>';
    }
    echo $output;
} 
//code for color

if(isset($_REQUEST['category_id']) && !empty($_REQUEST['category_id'])) {
    $sql = "SELECT * FROM `categories` WHERE `master` = ?";
    $statement = $objDb->prepare($sql);
    $statement->execute(array($_REQUEST['category_id']));
    $list = $statement->fetchAll(PDO::FETCH_ASSOC);
     if(!empty($list)) {
        $output = '<option value="">Select</option>';
        foreach($list as $row) {          
                $output .= '<option value="'.$row['id'].'">'.$row['name'].'</option>';
        }
    } else {
        $output = '<option value="">Select</option>';
    }
    echo $output;
}

希望这会对你有所帮助。

Answer 2

您将不得不编写一个JavaScript函数，从第一个HTML选择字段中检索所选的值或选项。此函数通常会写出当前页面的新URL路径，并添加一些连续的Get变量：

<script type="text/javascript">
getSelectedOptionValue() {
// create some variables to store your know values such as URL path and document
var myPath = " put the URL path to the current document here ";
var currentPage = "currentPage.php";
// get the values of any necessary select fields
var carMake = document.getElementById("carMake").value;

// write out the final URL with the Get Method variables you want using concatnitation
var getMethodURL = myPath + currentPage + "?carMake='" + carMake + "'";

// function refreshes page using the function made URL
window.location.replace( getMethodURL );
}
</script>

由于第二个选择字段取决于第一个，因此您必须假设用户将从第一个选项中进行选择。这意味着检索主选择字段值的函数必须运行以响应字段选择中的更改。例如

<select name="carMake" id="carMake" onchange="getSelectedOptionValue();">

根据您设置数据库的方式，您可能需要选项标记的值或用户在选项标记之间显示的字符串...这取决于您是否记住如何重新设置如果您的原始记录集尚未提取必要信息以编写第二组选择选项标记，则查询信息。

要使用php写出第二个选择字段，只需重复用于第一个的while循环。这次使用一个变量替换你的SQL语句，在该变量中使用get方法存储从新URL检索的值

<?php

// here I am using the more generic request method although you could use the get as well
$carMake = $_REQUEST['carMake'];

sql_secondSelectField = "SELECT * FROM tbl_carModels WHERE carMake = $carMake";

// Run new query and repeat similar while loop used to write your first select field ?>

PHP：可靠下拉菜单中所选项目的回声值

2 个答案: