PHP bindParam 和多个下拉菜单

Question

当在表单中选择性别时，我想在查询中添加 WHERE。

我正在使用 bindParam 使用一个下拉菜单来获取年份，但我想要第二个 bindParam 将“AND Gender =”插入查询并使用“$_GET['dropdowngender'] 来填充它。

我想使用 if 语句来查看是否正在使用下拉菜单以及是否选择了性别以表明信息正在添加到查询中。这是我到目前为止所拥有的，但它似乎不起作用。

<?php

@include ('conn.php');

$query = "SELECT Name, MAX(Count) AS MaxCount, ZIPcode, Year 
          FROM Name_Data 
          WHERE Year = :year ";
if( isset( $_GET['dropdowngender'] ) {
    $query = $query . " AND Gender = :gender ";
}

$query = $query . " AND Name_Data.Count = 
         ( SELECT MAX( Count ) FROM Name_Data AS f 
           WHERE f.id = Name_Data.id 
         ) GROUP BY ZIPcode";

$query->bindParam(':year', $_GET['dropdownyear'], PDO::PARAM_STR);
if( isset( $_GET['dropdowngender'] ) {
    $query->bindParam(':gender', $_GET['dropdowngender'], PDO::PARAM_STR);
}

$query_send = $db->prepare($query);

$query->execute();

$result = $query->fetchAll (PDO::FETCH_ASSOC);

$jsonResult = json_encode($result);

echo $jsonResult;

?>

我的索引页面

<form method="post" action="#" id="form">
        <select name="dropdownyear" id="menuyear">
            <option selected>Choose a year</option>
        </select>
        <select name="dropdowngender" id="menugender">
            <option value="M">Male</option>
            <option value="F">Female</option>
        </select>
</form>

我的 jquery 脚本

$( "#form" )
.change(function(){
$(".marker").empty();
var SelectYear= $("#menuyear option:selected").text();
var SelectGender= $("#menugender option:selected").text();

    $.getJSON( "sql.php",  { dropdownyear: SelectYear, dropdowngender: SelectGender }, function(jsonData) {    
        console.log( jsonData );

        $.each( jsonData, function(key,row) {
            var newDiv=$('<div>');
            var Content = row ['Name'] + ' ';
            newDiv.text(Content);
            newDiv.appendTo($("#result"));
    }); // each

    }); //get json
}); // change function

Answer 1

请添加您收到的错误消息，您是否打开了错误报告，有一些语法错误会立即停止程序。接下来，您正在对字符串调用 bindParam，这也不起作用；）。

(Zag dit toevallig op fb, gtz, d)

编辑：

这是未经测试的，但应该是这样的：

// I assume you have an instance of the pdo object? I will call it $db for convenience.
require_once 'conn.php';

$q = "SELECT Name, MAX(Count) AS MaxCount, ZIPcode, Year 
      FROM Name_Data 
      WHERE Year = :year";

if( isset( $_GET['dropdowngender'] ) && !empty( $_GET['dropdowngender']) ) {
    $q .= " AND Gender = :gender";
}

$q .= " AND Name_Data.Count = 
         ( SELECT MAX( Count ) FROM Name_Data AS f 
           WHERE f.id = Name_Data.id 
         ) GROUP BY ZIPcode";

$stmt = $db->prepare($q);
$stmt->bindParam(':year', $_GET['dropdownyear'], PDO::PARAM_STR);
if( isset( $_GET['dropdowngender'] ) && !empty( $_GET['dropdowngender']) ) {
    $stmt->bindParam(':gender', $_GET['dropdowngender'], PDO::PARAM_STR);
}
$stmt->execute();

$result = $stmt->fetchAll(PDO::FETCH_ASSOC);

$jsonResult = json_encode($result);

echo $jsonResult;