如果选中复选框，如何回显“选中”

Question

在表单的“编辑视图”中，我有一个复选框列表，我想检查表book_have_languages中的复选框(请注意，一本书可以有多种语言)。

代码：

<?php $query_c = mysqli_query($mysqli, "SELECT id_language, name_language FROM languages ORDER BY name_language;")
                                                        or die('error '.mysqli_error($mysqli));
while ($data_c = mysqli_fetch_assoc($query_c)) {
      echo "<div class='checkbox'><label><input type='checkbox' name='languages[]' value='$data_c[id_languages]'>$data_c[name_language]</label></div>";

      $sql = "SELECT id_book, id_language FROM book_have_languages WHERE id_book=3";
      $res = $mysqli->query($sql) or die("error: ".$sql);
      $results = array();
      while($row = mysqli_fetch_assoc($res)) {
         $results[] = $row;
      }
      foreach ($results as $result){
       if($result['id_language'] == $data_c['id_language']){
        echo"<div class='checkbox'><label><input type='checkbox' name='languages[]' value='$data_c[id_language]'checked >$data_c[name_language]</label></div>";
       }

      }


}
?>

结果：

如果我的桌子是：

id_book x- id_language

3-2

3-5

3-6

检查语言2、5、6，但它们看起来是重复的。如何在第一个回显中只显示表中没有的语言？

Answer 1

你在浏览各种语言，而不是通过一本书所拥有的语言。如果您的表如所描述的那样，$data_idi应该有多个结果，并且只匹配第一个结果。您也应该在这些结果中循环。

Answer 2

我就是这样解决的：

<?php
$query_c = mysqli_query($mysqli, "SELECT id_language, name_language FROM languages ORDER BY name_language;")
                                    or die('error '.mysqli_error($mysqli));

while ($data_c = mysqli_fetch_assoc($query_c)) {
      $sql = "SELECT id_book, id_language FROM book_te_languages WHERE id_book='$_GET[id]'";
      $res = $mysqli->query($sql) or die("error: ".$sql);
      $results = array();
      while($row = mysqli_fetch_assoc($res)) {
         $results[] = $row;
      }

    echo "<div class='checkbox'><label><input type='checkbox' name='languages[]' value='$data_c[id_language]'";
    foreach ($results as $result){
       if($result['id_language'] == $data_c['id_language']){
         echo "checked";
       }
    } 
    echo ">$data_c[name_language]</label></div>"; 
}
?>