我有以下php代码从另一个页面接收一些变量（通过POST发送）。
根据Ad_id和姓名...我正在尝试在“有效”或“无效”之间切换状态。
然而，当我执行此操作时（使用正确的POST数据）...它似乎没有更新任何内容。我做错了什么？
e.g。当我通过有效广告发送时，请输入姓名＆amp; status ...然后去查看JSON文件，它没有将'active'切换为'inactive'。
PHP：
<?php
// Get the post variables
$ad_id = $_GET['ad'];
$name = $_GET['name'];
$status = $_GET['status'];
// Get the JSON file
$json = file_get_contents('test.json');
// Decode Json into an array
$json = json_decode($json,true);
// Within the array.. find the ad that matches the POST variable.
foreach ($json['ads'] as $ad) {
if ($ad['id'] == $ad_id) {
// Within that Ad... find the candidate that matches the POST variable.
foreach ($ad['candidates'] as $candidate) {
if ($candidate['name'] == $name) {
// Within that candidate... check the value of 'status'.
if ($candidate['status'] == 'active') {
// If active, update the status to 'inactive'.
$candidate['status'] = 'inactive';
} else {
// If inactive, update the status to 'active'.
$candidate['status'] = 'active';
}
}
}
}
}
// Encode the array as JSON again
$json = json_encode($json);
// Save the JSON back to the server
file_put_contents('test.json', $json, LOCK_EX);
?>
JSON：
{
"ads": [
{
"id": "12345678",
"hirername": "Demo Bar",
"candidates": [
{
"status": "active",
"name": "Gregory Jones",
"dist": "Richmond (4km away)",
"exp1": "Barman at City Bar for 2 years",
"avail1": "Mon to Fri - Morning, Evening & Night",
"visa": "Australian Citizen",
"call": "0413451222"
},
{
"status": "active",
"name": "Jackie Linton",
"dist": "Box Hill (13km away)",
"exp1": "Bar girl at Collins Bar for 1 year",
"avail1": "Mon to Fri - Morning & Evening",
"visa": "Working holiday visa",
"call": "0413456555"
}
]
}
]
}
答案 0 :(得分：1)
您应该使用foreach($items as &$item)语法链接来迭代数据
然后所有更改都将在原始结构中。
现在，您可以创建副本，同时进行迭代，修改副本，并且不做任何更改。
// Get the post variables
$ad_id = $_GET['ad'];
$name = $_GET['name'];
$status = $_GET['status'];
// Get the JSON file
$json = file_get_contents('test.json');
// Decode Json into an array
$json = json_decode($json,true);
// Within the array.. find the ad that matches the POST variable.
foreach ($json['ads'] as &$ad) {
if ($ad['id'] == $ad_id) {
// Within that Ad... find the candidate that matches the POST variable.
foreach ($ad['candidates'] as &$candidate) {
if ($candidate['name'] == $name) {
// Within that candidate... check the value of 'status'.
if ($candidate['status'] == 'active') {
// If active, update the status to 'inactive'.
$candidate['status'] = 'inactive';
} else {
// If inactive, update the status to 'active'.
$candidate['status'] = 'active';
}
}
}
}
}
// Encode the array as JSON again
$json = json_encode($json);
// Save the JSON back to the server
file_put_contents('test.json', $json, LOCK_EX);
答案 1 :(得分：0)
您的代码中有错误。您为阅读和比较值所做的工作是正确的。
但在写作时，您尚未使用 import javax.swing.JOptionPane;
public class MusicPlaylist {
// the maximum number of songs the music playlist can hold
public static final int MAX_SONGS = 3;
public static void main(String[] args) {
// create arrays and size counter
int size = 0;
String[] songsTitles = new String[MAX_SONGS];
double[] songsLength = new double[MAX_SONGS];
// Enter Songs
while (true) {
// check max number of songs
if (size >= MAX_SONGS) {
JOptionPane.showMessageDialog(null, "Max number of songs reached.");
break;
}
// Get title or exit command
String title = JOptionPane
.showInputDialog("Insert song #" + (size + 1) + " title (or Cancel to finish adding songs):");
if (title == null)
break;
// check if there is a title
if (title.isEmpty()) {
JOptionPane.showMessageDialog(null, "Title must not be null.", "Error", JOptionPane.ERROR_MESSAGE);
continue; // start from the top
break;
}
// Get length
double length;
try {
length = Double
.parseDouble(JOptionPane.showInputDialog("Insert song" + (size + 1) + " length is minutes: "));
if (length <= 0)
throw new NumberFormatException();
} catch (NumberFormatException e) {
JOptionPane.showMessageDialog(null, "Length must not be a valid, posite double number.", "Error",
JOptionPane.ERROR_MESSAGE);
continue; // start from the top
}
// Add song
songsTitles[size] = title;
songsLength[size++] = length;
}
// show list and allow to remove songs
while (size > 0) { // if size <=0, nothing to remove
// show list
String list = "";
for (int i = 0; i < size; i++) {
list += songsTitles[i] + " '+ songsLength[i] + 'min/n";
}
JOptionPane.showMessageDialog(null, list);
// get title or exit command
String title = JOptionPane.showInputDialog("Insert title to delete(or Cancel to finish removing songs):");
if (title == null)
break;
// Find and delete song or show error message
boolean found = false;
for (int i = 0; i < size; i++) {
if (songsTitles[i].equals(title))
// Delete song by shifting following songs over it in the
// array
for (int j = i + 1; j < size; j++) {
songsTitles[j - 1] = songsTitles[j];
songsLength[j - 1] = songsLength[j];
}
size--;
found = true;
}
}
**if (!found) {**
JOptionPane.showMessageDialog(null, "Song not found", "Error", JOptionPane.ERROR_MESSAGE);
}
// Show report
String list = "*** REPORT ***/n";
double total = 0;
for (int i = 0; i < size; i++) {
list += songsTitles[i] + " " + songsLength[i] + "mins/n";
total += songsLength[i];
}
list += "/nTotal length: " + total + " minutes.";
JOptionPane.showMessageDialog(null, list);
}
}
变量的状态。
你正在写作。
$json上面你使用变量if ($candidate['status'] == 'active') {
$candidate['status'] = 'inactive';
} else {
$candidate['status'] = 'active';
}
。
写入文件时，
$candidate修改
$json = json_encode($json); <------- $json is used. Where is $candidate??
$ret = file_put_contents('test.json', $json, LOCK_EX);
答案 2 :(得分：0)
/**
* Problem:
*
* - We have 2 variables
* $adId: The id of the ad
* $name: The name of the candidate
*
* - We want to update the status of the candidate depending the current status
*/
// Fake JSON datas
$json = '{
"ads": [
{
"id": "238",
"hirername": "Demo Bar",
"candidates": [
{
"status": "active",
"name": "Gregory Jones"
},
{
"status": "active",
"name": "Jackie Linton"
}
]
},
{
"id": "239",
"hirername": "Apple",
"candidates": [
{
"status": "inactive",
"name": "Steve jobs"
}
]
}
]
}';
// Input variables
$adId = 238;
$name = 'Jackie Linton';
// Convert json as an array (we use true as a second param for that)
$data = json_decode($json, true);
// We fetch only the ads entity from the array
$ads = $data['ads'];
// Loop the ads
foreach ($ads as $adIndex => $ad)
{
// Check if it's the right ad
if ($ad['id'] == $adId)
{
// Loop candidates
foreach ($ad['candidates'] as $candidateIndex => $candidate)
{
// Sanitize strings for a good check
$name = trim(strtolower($name));
$candidateName = trim(strtolower($candidate['name']));
// We found the right candidate
if ($name == $candidateName)
{
// Change status
if ($candidate['status'] == 'inactive')
{
$data['ads'][$adIndex]['candidates'][$candidateIndex]['status'] = 'active';
}
else
{
$data['ads'][$adIndex]['candidates'][$candidateIndex]['status'] = 'inactive';
}
}
}
}
}
// We changed the status.
echo '<pre>';
var_dump($data);
echo '</pre>';
使用该代码（经过测试和工作），您将了解您的问题： - 您将数据保存在“本地”变量而不是全局JSON中。