Question

我有这段代码：

foreach($this->authors as $autor){

    if($autor->author == $filter_autor){
        echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

    }else{
        echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
      }
};

作者可能会重复多次。我怎么能改变这个代码，使它只打印每一个重复显示一次的代码？

提前感谢您的帮助。

Answer 1

未经测试，但试试这个：

foreach(array_unique($this->authors) as $autor){

    if($autor->author == $filter_autor){
        echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

    }else{
        echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
      }
};

Answer 2

$var = '';
foreach($this->authors as $autor){

    if($var != $autor->author)
    {
       if($autor->author == $filter_autor){
           echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

       }else{
           echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
        }
    }
    $var = $autor->author;

};

Answer 3

最好的选择是在开始输出之前过滤数组。

如果这是不可能的，无论出于何种原因（包括个人偏好），尝试这样的事情：

$used_authors = array();
foreach($this->authors as $autor){
  if(!isset($used_authors[$autor->author]){
    if($autor->author == $filter_autor){
        echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

    }else{
        echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
    }
    $used_authors[$autor->author] = true;
  }
};

Answer 4

希望这会对你有所帮助

$newarray=array_unique($this->authors);
    foreach($newarray as $autor){

        if($autor->author == $filter_autor){
            echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

        }else{
            echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
          }
    }

了解array_unique()

Answer 5

希望这会对你有所帮助

 $unieq_array=array_unique($this->authors);

        foreach($unieq_array as $autor){

            if($autor->author == $filter_autor){
                echo '<option value="'.$autor->author.'" selected="selected">'.$autor-     >author.'</option>';

            }else{
                echo '<option value="'.$autor->author.'">'.$autor->author.'</option>';
              }
        };

如何在PHP中显示一次重复值

5 个答案: