Question

我有一个带有＆＃39;类别的对象数组＆＃39;属性。我需要得到一个不同类别的列表，我怎么能这样做，因为我有一个方法从对象中获取类别？下面显示的是创建数组中所有类别的列表，但显然有很多重复的类别：

    foreach (getSourceCodes() as $source) {
        echo $source->getCategory();
    }

Answer 1

您可以在php中使用array_unique()。

$categories = array();
foreach (getSourceCodes() as $source) {
    array_push($categories, $source->getCategory());
}
$categories = array_unique($categories);

如果类别是多维的，那么使用此方法将其序列化，然后获取唯一数组，然后将其更改回数组。

$categories = array_map("unserialize", array_unique(array_map("serialize", $categories)));

Answer 2

如果您将类别用作数组键，则根据定义它将是唯一的。

foreach (getSourceCodes() as $source) {
    // The value is irrelevant. You can use a counter if you want to keep track of that.
    $an_array[$source->getCategory()] = true;
    // The key is just overwritten for duplicate values of getCategory()
}

// Then you can use array_keys to get the keys as values.
var_dump(array_keys($an_array));

Answer 3

不确定列表的格式是什么，但假设使用逗号分隔值...

$aCategories = array();
$aList = array();

    foreach (getSourceCodes() as $source) {
          // Get categories as comma separated string list???
           $sList = $source->getCategory();

           // Convert string list to array
           $aTmpList = explode(",",$sList);

           //Check temp list against current list for new categories
           $aDiffList = array_diff($aList,$atmpList);

           //Merge new categories into current list
            $aList = array_merge($aDiffList,$aList);
       }
       // Convert array to string list
       $sCategories = implode(",", $aList);

如何从对象中获取唯一属性的列表

3 个答案: