Php 基于用户输入编写包含变量WHERE的查询

我有个疑问。我希望它做的是检查每个变量是否存在，如果不存在，则忽略它们。我还想在表格中显示结果。任何帮助都将不胜感激

到目前为止我所拥有的：这是我的代码。目前，它返回一个包含数据库所有结果的数组，但如果我将WHERE子句中的ORs更改为AND，则需要填充所有字段。我希望用户能够输入尽可能多的信息，以便显示所有可能的结果

<?php require("common.php");?>
<?php
if(!empty($_POST))
{
$sth = $db->prepare("SELECT * FROM customer WHERE First_name LIKE '%$First_name%' OR Surname LIKE '%$Surname%' OR DOB LIKE '$DOB' OR Street LIKE '%$Street%' OR Suburb LIKE '$Suburb' OR State LIKE '$State' OR Postcode LIKE '$Postcode' OR Phone LIKE '$Phone'");
$sth->execute();

/* Fetch all of the remaining rows in the result set */
print("Fetch all of the remaining rows in the result set:\n");
$result = $sth->fetchAll();
print_r($result);



$First_name = $_POST['First_name'];
$Surname = $_POST['Surname'];
$DOB = $_POST['DOB'];
$Street = $_POST['Street'];
$Suburb = $_POST['Suburb'];
$State = $_POST['State'];
$Postcode = $_POST['Postcode'];
$Phone = $_POST['Phone'];
}
?>
<fieldset><legend>Find a customer</legend>
<form name="querycustomerform" method="post" action="qcustomer.php">
    <table class="five">
        <tr>
            <td colspan="4">
                <h3>Please fill out as many details as possible</h3>
            </td>
        </tr>
        <tr>
            <td>
                <input type="text" name="First_name" maxlength="30" size="30" placeholder="First name">
            </td>
            <td>
                <input type="text" name="Surname" maxlength="30" size="30" placeholder="Surname">
            </td>
            <td style="text-align: right">Date of Birth:</td>
            <td>
                <input type="date" name="DOB">
            </td>
        </tr>
        <tr>
            <td>
                <input type="text" name="Street" maxlength="40" size="30" placeholder="Street Address">
            </td>
            <td>
                <input type="text" name="Suburb" maxlength="15" size="30" placeholder="Suburb">
            </td>
            <td>
                <select name="State">
                <option value="">State</option>
                <option value="ACT">Australian Capital Territory</option>
                <option value="NSW">New South Wales</option>
                <option value="NT">Northern Territory</option>
                <option value="QLD">Queensland</option>
                <option value="SA">South Australia</option>
                <option value="TAS">Tasmania</option>
                <option value="VIC">Victoria</option>
                <option value="WA">Western Australia</option>
                </select>
            </td>
            <td>
                <input type="text" name="Postcode" maxlength="4" size="30" placeholder="Postcode">
            </td>
        </tr>
        <tr>
            <td>
                <input type="text" name="Phone" maxlength="15" size="30" placeholder="Phone Number">
            </td>
            <td>
            </td>
            <td>
            </td>
            <td>
                <input class="button" type="submit" value="Search">
            </td>
        </tr>
    </table> 
</form>
</fieldset>

试着改变

$sth = $db->prepare("SELECT * FROM customer WHERE First_name LIKE '%$First_name%' OR Surname LIKE '%$Surname%' OR DOB LIKE '$DOB' OR Street LIKE '%$Street%' OR Suburb LIKE '$Suburb' OR State LIKE '$State' OR Postcode LIKE '$Postcode' OR Phone LIKE '$Phone'");

到

从文本字符串中提取$First_name，并将其与文本字符串连接起来。您所做的是逐字搜索“$First_name”，而不是$First_name变量的值。从外观的角度来看，这有点混乱，但我发现将文本与变量连接起来比在引号中展开变量更安全

Darryl
或条件要求任何条件（即：条件1、条件2、条件n）必须满足才能将记录包括在结果集中。而和条件要求所有条件（即：条件1、条件2、条件n）必须满足这些要求。对于您的要求，或条件是必需的

您需要构建一个动态查询来执行此操作。从基本存根开始

$sql = "SELECT * FROM customer";

然后需要将初始子句设置为WHERE

$clause = " WHERE ";//Initial clause

您需要一个数组来存储参数

$paramArray =array();

开始构建查询。注意，我已从POST更改为GET，因为它更易于测试
另请参见占位符中的使用%。ie占位符不能表示查询的任意部分，而只能表示完整的数据文字

if(isset($_GET['First_name'])){
    $First_name = $_GET['First_name'];
    $sql .= "$clause First_name LIKE ?";
    $clause = " OR ";//Change clause
    array_push($paramArray,"%$First_name%");
}   

继续下一条

if(isset($_GET['Surname'])){
    $Surname = $_GET['Surname'];
    $sql .= "$clause Surname LIKE ?";
    $clause = " OR ";
    array_push($paramArray,"%$Surname%");
}   

增加上述条款的剩余部分

测试结果，测试后移除，更改后发布

echo $sql ;
echo "<br>";
print_r($paramArray);

Test.php？First_name=dave&name=smith的典型测试结果

SELECT * FROM customer WHERE First_name LIKE ? OR Surname LIKE ?
Array ( [0] => %dave% [1] => %smith% )

SELECT * FROM customer WHERE Surname LIKE ?
Array ( [0] => %smith% )

来自
test.php？姓氏=smith

SELECT * FROM customer WHERE First_name LIKE ? OR Surname LIKE ?
Array ( [0] => %dave% [1] => %smith% )

SELECT * FROM customer WHERE Surname LIKE ?
Array ( [0] => %smith% )

检查填写的内容，添加到查询中是否提供了信息，以及该信息是什么样子？