我正在尝试编写的递归函数出现问题。在这里你可以看到我的代码：
function getParents($individualInfo) {
$individualid = '';
if(is_array($individualInfo)) {
foreach($individualInfo as $key => $value) {
if(is_array($individualInfo[$key])) {
return $this->getParents($individualInfo[$key]);
}
else {
if ($key == 'individual_id') {
$individualid = $individualInfo[$key];
}
}
}
}
else {
$individualid = $individualInfo;
}
$q = "SELECT i.individual_id, i.fname, i.lname, i.birth_date, i.death_date, i.gender,
i.biography, i.avatar, i.individual_username, r.relationship_individual
FROM ".TBL_RELATIONSHIPS." AS r, ".TBL_INDIVIDUALS." AS i
WHERE r.relationship_individual = '$individualid'
AND r.individual = i.individual_id
AND (r.role = '2')
LIMIT 2";
$result = $this->database->query($q);
if ($result === false) {
$result .= die(mysql_error());
return;
}
$num_rows = mysql_num_rows($result);
$tmp_array = array();
if ($num_rows > 0) {
while ($row = mysql_fetch_assoc($result)) {
$tmp_array[] = $row;
}
foreach ($tmp_array as $tmp_parents) {
$tmp_parents['individual_id'] = $this->database->cleanOutput($tmp_parents['individual_id']);
$tmp_parents['fname'] = $this->database->cleanOutput($tmp_parents['fname']);
$tmp_parents['lname'] = $this->database->cleanOutput($tmp_parents['lname']);
$tmp_parents['birth_date'] = $this->database->cleanOutput($tmp_parents['birth_date']);
$tmp_parents['death_date'] = $this->database->cleanOutput($tmp_parents['death_date']);
$tmp_parents['gender'] = $this->database->cleanOutput($tmp_parents['gender']);
$tmp_parents['biography'] = $this->database->cleanOutput($tmp_parents['biography']);
$tmp_parents['avatar'] = $this->database->cleanOutput($tmp_parents['avatar']);
$tmp_parents['individual_username'] = $this->database->cleanOutput($tmp_parents['individual_username']);
$tmp_parents['relationship_individual'] = $this->database->cleanOutput($tmp_parents['relationship_individual']);
// father
if (!isset($parents[0]) && $tmp_parents['gender'] == 'Male') {
$parents[0] = $tmp_parents;
}
// mother
else {
$parents[1] = $tmp_parents;
}
}
return $parents;
}
}
$this->getParents($this->getParents($individualid));
如果只传递了id，则输出如下所示，例如160：
Array ( [0] => Array ( [individual_id] => 161 [fname] => John [lname] => Doe [birth_date] => [death_date] => [gender] => Male [biography] => [avatar] => [individual_username] => [relationship_individual] => 160 ) [1] => Array ( [individual_id] => 162 [fname] => Jane [lname] => Doe [birth_date] => [death_date] => [gender] => Female [biography] => [avatar] => [individual_username] => [relationship_individual] => 160 ) )
如果我将上面发布的数组传递给函数，我想得到这些结果：
Array ( [0] => Array ( [individual_id] => 163 [fname] => Sr. John [lname] => Doe [birth_date] => [death_date] => [gender] => Male [biography] => [avatar] => [individual_username] => [relationship_individual] => 161 ) [1] => Array ( [individual_id] => 164 [fname] => Sr. Jane [lname] => Doe [birth_date] => [death_date] => [gender] => Female [biography] => [avatar] => [individual_username] => [relationship_individual] => 161 ) )
Array ( [0] => Array ( [individual_id] => 165 [fname] => Sr. John [lname] => Roe [birth_date] => [death_date] => [gender] => Male [biography] => [avatar] => [individual_username] => [relationship_individual] => 162 ) [1] => Array ( [individual_id] => 166 [fname] => Sr. Jane [lname] => Roe [birth_date] => [death_date] => [gender] => Female [biography] => [avatar] => [individual_username] => [relationship_individual] => 162 ) )
上述功能应该帮助我找到任何特定个体或一系列个体的父母。例如，如果传递了包含父项的数组，则返回祖父母的所有数据。现在，该函数不会返回所有结果，因为我在第一个foreach循环中使用了return语句，而函数只能返回一次。但是，如果我不使用return，则返回null，因为此时$ individualid是一个空字符串。显示信息的功能如下所示：
function displayParents($parentsInfo) {
foreach ($parentsInfo as $parents) {
// father
if (isset($parents[0])) {
$type = 'father';
$individualid = $parents[0]['individual_id'];
$name = $parents[0]['fname'].' '.$parents[0]['lname'];
$bdate = $parents[0]['birth_date'];
$ddate = $parents[0]['death_date'];
$gender = $parents[0]['gender'];
$bio = $parents[0]['biography'];
$avatar = $parents[0]['avatar'];
$username = $parents[0]['individual_username'];
$relationshipid = $parents[0]['relationship_individual'];
$this->displayLeaf($type, $individualid, $name, $gender, $bdate, $ddate, $bio, $avatar, $username, $relationshipid);
}
else {
$type = 'emptyFather';
$this->displayLeaf($type, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
// mother
if (isset($parents[1])) {
$type = 'mother';
$individualid = $parents[1]['individual_id'];
$name = $parents[1]['fname'].' '.$parents[1]['lname'];
$bdate = $parents[1]['birth_date'];
$ddate = $parents[1]['death_date'];
$gender = $parents[1]['gender'];
$bio = $parents[1]['biography'];
$avatar = $parents[1]['avatar'];
$username = $parents[1]['individual_username'];
$relationshipid = (isset($parents[0]) ? $parents[0]['individual_id'] : $parents[1]['relationship_individual']);
$this->displayLeaf($type, $individualid, $name, $gender, $bdate, $ddate, $bio, $avatar, $username, $relationshipid);
}
else {
$type = 'emptyMother';
$this->displayLeaf($type, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
}
}
我试图寻找我的问题的答案，但我找不到任何解决方案，因为我真的很陌生。有关如何更改功能以使其完全符合我需要的任何建议吗？
答案 0 :(得分：0)
你真的需要递归吗？
我并不是100％清楚你期望什么样的输出，如果它只是输入中所有父母的平面阵列，那么你可以很容易地做到。
function getParents($individualInfo) {
if ( is_integer($individualInfo)) { $individualInfo = array('individual_id' => $individualInfo); }
if ( isset($individualInfo['individual_id'])) { $individualInfo = array($individualInfo); }
/* input is now consistently an array of associative arrays that should have a key 'individual_id' */
$ids = array();
foreach ($individualInfo as $individual)
{
if (!empty($individual['individual_id']) && is_integer($individual['individual_id']) )
{
$ids[$individual['individual_id']] = true;
/* I'm doing this instead of simply adding the id to the array
so I can get just the unique ids from the array_keys later*/
}
}
$idsstring = implode(',', array_keys($ids));
$maxparents = 2*count($ids); /* Well, assuming nuclear families */
/* there might not be any ids for some reason (like bad input) */
if (empty($idsstring))
{
return array();
}
/* we've checked that all ids are integers, so there is little risk of SQL-injection
* With `r.relationship_individual IN ($idsstring)` we can search for all parents of
* all individuals at once.
*/
$q = "SELECT i.individual_id, i.fname, i.lname, i.birth_date, i.death_date, i.gender,
i.biography, i.avatar, i.individual_username, r.relationship_individual
FROM ".TBL_RELATIONSHIPS." AS r, ".TBL_INDIVIDUALS." AS i
WHERE r.relationship_individual IN ($idsstring)
AND r.individual = i.individual_id
AND (r.role = '2')
LIMIT $maxparents";
$result = $this->database->query($q);
if ($result === false) {
$result .= die(mysql_error());
return;
}
$num_rows = mysql_num_rows($result);
$tmp_array = array();
$parents = array();
if ($num_rows > 0) {
while ($row = mysql_fetch_assoc($result)) {
$tmp_array[] = $row;
}
foreach ($tmp_array as $tmp_parents) {
foreach($tmp_parents as $key => $value){
$tmp_parents[$key] = $this->database->cleanOutput($value);
}
$parents[] = $tmp_parents;
}
}
return $parents;
}
另一方面，如果你想建立一个父母父母的父树，那么递归可能是有序的。 （尽管从数据库中获取父母的信息仍然是最好的避免。一次查询数据库效率更高。）现在，如果是这样的话，请允许我。