我遇到问题使这段代码有效：
index.php:
<?php
include("config.php");
$asd=123;
$db = new db();
$db->connect();
$db->sql('SELECT id,name FROM CRUDClass');
$res = $db->getResult();
foreach($res as $output){
echo '<div>'.$output['name'].' - <a href="" onclick="'.$db->delete('CRUDClass','id='.$output['id']).'">Delete ID: '.$output['id'].'</a></div><br>';
}
?>
config.php
<?php
class db{
private $result = array();
private $myQuery = "";
private $numResults = "";
....
public function sql($sql){
$query = @mysql_query($sql);
$this->myQuery = $sql; // Pass back the SQL
if($query){
// If the query returns >= 1 assign the number of rows to numResults
$this->numResults = mysql_num_rows($query);
// Loop through the query results by the number of rows returned
for($i = 0; $i < $this->numResults; $i++){
$r = mysql_fetch_array($query);
$key = array_keys($r);
for($x = 0; $x < count($key); $x++){
// Sanitizes keys so only alpha-values are allowed
if(!is_int($key[$x])){
if(mysql_num_rows($query) >= 1){
$this->result[$i][$key[$x]] = $r[$key[$x]];
}else{
$this->result = null;
}
}
}
}
return true; // Query was successful
}else{
array_push($this->result,mysql_error());
return false; // No rows where returned
}
}
// Function to SELECT from the database
public function select($table, $rows = '*', $join = null, $where = null, $order = null, $limit = null){
// Create query from the variables passed to the function
$q = 'SELECT '.$rows.' FROM '.$table;
if($join != null){
$q .= ' JOIN '.$join;
}
if($where != null){
$q .= ' WHERE '.$where;
}
if($order != null){
$q .= ' ORDER BY '.$order;
}
if($limit != null){
$q .= ' LIMIT '.$limit;
}
$this->myQuery = $q; // Pass back the SQL
// Check to see if the table exists
if($this->tableExists($table)){
// The table exists, run the query
$query = @mysql_query($q);
if($query){
// If the query returns >= 1 assign the number of rows to numResults
$this->numResults = mysql_num_rows($query);
// Loop through the query results by the number of rows returned
for($i = 0; $i < $this->numResults; $i++){
$r = mysql_fetch_array($query);
$key = array_keys($r);
for($x = 0; $x < count($key); $x++){
// Sanitizes keys so only alphavalues are allowed
if(!is_int($key[$x])){
if(mysql_num_rows($query) >= 1){
$this->result[$i][$key[$x]] = $r[$key[$x]];
}else{
$this->result = null;
}
}
}
}
return true; // Query was successful
}else{
array_push($this->result,mysql_error());
return false; // No rows where returned
}
}else{
return false; // Table does not exist
}
}
// Function to insert into the database
public function insert($table,$params=array()){
// Check to see if the table exists
if($this->tableExists($table)){
$sql='INSERT INTO `'.$table.'` (`'.implode('`, `',array_keys($params)).'`) VALUES ("' . implode('", "', $params) . '")';
$this->myQuery = $sql; // Pass back the SQL
// Make the query to insert to the database
if($ins = @mysql_query($sql)){
array_push($this->result,mysql_insert_id());
return true; // The data has been inserted
}else{
array_push($this->result,mysql_error());
return false; // The data has not been inserted
}
}else{
return false; // Table does not exist
}
}
//Function to delete table or row(s) from database
public function delete($table,$where = null){
// Check to see if table exists
if($this->tableExists($table)){
// The table exists check to see if we are deleting rows or table
if($where == null){
$delete = 'DELETE '.$table; // Create query to delete table
}else{
$delete = 'DELETE FROM '.$table.' WHERE '.$where; // Create query to delete rows
}
// Submit query to database
if($del = @mysql_query($delete)){
array_push($this->result,mysql_affected_rows());
$this->myQuery = $delete; // Pass back the SQL
return true; // The query exectued correctly
}else{
array_push($this->result,mysql_error());
return false; // The query did not execute correctly
}
}else{
return false; // The table does not exist
}
}
....
public function getResult(){
$val = $this->result;
$this->result = array();
return $val;
}
//Pass the SQL back for debugging
public function getSql(){
$val = $this->myQuery;
$this->myQuery = array();
return $val;
}
//Pass the number of rows back
public function numRows(){
$val = $this->numResults;
$this->numResults = array();
return $val;
}
}
?>
问题在于，当我尝试删除列表中的项目时，它会删除数据库中的所有项目。我可以使用链接中的$ get [＆＃39; id＆＃39;]方法在单独的文件中正确删除项目，但我不明白为什么当前的代码会在foreach中搞砸了？
答案 0 :(得分：0)
在此：
echo '<div>'.$output['name'].' - <a href="" onclick="'.$db->delete('CRUDClass','id='.$output['id']).'">Delete ID: '.$output['id'].'</a></div><br>';
您希望在触发onclick事件时调用delete方法，但这不会发生。
目前，访问index.php时将调用delete方法。
要使其正常工作，请将<a>标记更改为链接到其他php文件并将调用放在其中的delete方法中，或者您可以在链接中使用相同的php文件并使用？查询链接。
答案 1 :(得分：0)
到底是什么，你完全误解了PHP xD
让我们说你的代码insert, delete,...按照你想要的方式工作，而不是：
foreach($res as $output){
echo '<div>'.$output['name'].' - <a href="" onclick="'.$db->delete('CRUDClass','id='.$output['id']).'">Delete ID: '.$output['id'].'</a></div><br>';
}
...生成一些<div>Name <a href="" onclick="'true'">Delete ID: 1</a></div><br>代码。创建后，每个delete都被调用，因此你的表是空的。
PHP仅在服务器上生成输出并将其发送回客户端。你必须写这样的代码：
foreach(...) {
?>
<div><a href="delete.php?id=<?=$output['id']?>">delete me</a></div>
<?php
}
然后在delete.php中，您$_GET['id']并致电delete。
总而言之，阅读http://en.wikipedia.org/wiki/SQL_injection永远不会太早。这意味着您必须在将id参数插入查询之前将其转义。我建议使用准备好的陈述。
但首先，了解PHP的作用:)。您无法将PHP回调实现为HTML或您尝试过的内容。