如何在 android 中 POST 参数并将数据作为 JSONObject 返回？
How to POST params in android and GET data back as JSONObject?
我必须 POST 用户名、密钥和另一个参数才能将数据作为 JSONObject 获取并在 RecyclerView 中显示它们。我在 android 中使用 Volley Library，尝试了所有可能的方法 none，其中有帮助..
尽管通过 Postman 进行测试似乎工作正常，并且当我 post 这三个参数时我得到了数据，但我不知道我在 android..
中遗漏了什么
PHP代码：
<?php
require("db/Db.class.php");
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getMainCategory'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$catigory = $db->query("SELECT * FROM `oc_category_description`,oc_category WHERE oc_category_description.category_id = oc_category.category_id and oc_category.status = 1 and oc_category.parent_id = 0 and oc_category_description.language_id = 2");
$json = $catigory;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getSlideShow'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$slideShowId = (int)$_POST['getSlideShow'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$banderSlideShow = $db->query("SELECT * FROM `oc_banner_image` where `banner_id` = $slideShowId and language_id = 2");
$json = $banderSlideShow;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getAllNews'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$catigory = $db->query("SELECT * FROM `oc_blog_article`,`oc_blog_article_description` WHERE oc_blog_article_description.blog_article_id = oc_blog_article.blog_article_id and oc_blog_article.status = 1 and oc_blog_article_description.language_id = 2 order by oc_blog_article.sort_order");
$json = $catigory;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
$json = ["error"];
header('Content-Type: application/json');
echo json_encode($json);
?>
JAVA代码：
public static final String URL_PRODUCTS = "http://vinsmartangle.net/shop/myApi/index.php";
private void loadProducts(final String user, final String api,final String no) {
StringRequest stringRequest = new StringRequest(Request.Method.POST, URL_PRODUCTS,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
//converting the string to json array object
JSONArray array = new JSONArray(response);
//traversing through all the object
for (int i = 0; i < array.length(); i++) {
//getting product object from json array
JSONObject category = array.getJSONObject(i);
String id = category.getString("category_id");
String name = category.getString("name");
Category data = new Category();
//adding the product to product list
data.setCategoryNo(id);
data.setCategoryName(name);
categoryList.add(data);
}
categoryAdapter = new CategoryAdapter(getActivity(),categoryList, Fragment_Payment.this);
recyclerView.setAdapter(categoryAdapter);
} catch (JSONException e) {
e.printStackTrace();
}
catch (JsonParseException e)
{
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.d(TAG, "onErrorResponse: Error ", error.getCause());
}
})
{
@Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("username ",user);
params.put("key",api);
params.put("getMainCategory",no);
return params;
}
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/json");
return headers;
}
};
//adding our stringrequest to queue
Volley.newRequestQueue(getActivity()).add(stringRequest);
}
邮递员Screenshot:
[
{
"category_id": "20",
"language_id": "2",
"name": "رمان",
"description": "<p><br><\/p>",
"meta_title": "رمان",
"meta_description": "مثال لوصف القسم",
"meta_keyword": "",
"image": "catalog\/demo\/compaq_presario.jpg",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "1",
"status": "1",
"date_added": "2009-01-05 21:49:43",
"date_modified": "2019-07-03 01:53:35"
},
{
"category_id": "83",
"language_id": "2",
"name": "خضروات",
"description": "",
"meta_title": "خضروات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "2",
"status": "1",
"date_added": "2019-07-04 11:05:33",
"date_modified": "2019-07-05 06:16:54"
},
{
"category_id": "85",
"language_id": "2",
"name": "ورقيات",
"description": "",
"meta_title": "ورقيات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "0",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:06:41",
"date_modified": "2019-07-04 11:06:41"
},
{
"category_id": "90",
"language_id": "2",
"name": "عسل",
"description": "",
"meta_title": "عسل",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:08:56",
"date_modified": "2019-07-05 11:59:46"
},
{
"category_id": "87",
"language_id": "2",
"name": "صناديق",
"description": "",
"meta_title": "صناديق",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:07:43",
"date_modified": "2019-07-05 11:59:30"
},
{
"category_id": "57",
"language_id": "2",
"name": "فواكة موسمية",
"description": "<p><br><\/p>",
"meta_title": "فواكة موسمية",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "3",
"status": "1",
"date_added": "2011-04-26 08:53:16",
"date_modified": "2019-07-03 01:52:47"
},
{
"category_id": "89",
"language_id": "2",
"name": "مشروبات",
"description": "",
"meta_title": "مشروبات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "0",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:08:01",
"date_modified": "2019-07-04 11:08:01"
}
]
当我 运行 应用程序时，我得到这个异常：
W/System.err: org.json.JSONException: Value error at 0 of type java.lang.String cannot be converted to JSONObject
at org.json.JSON.typeMismatch(JSON.java:101)
at org.json.JSONArray.getJSONObject(JSONArray.java:525)
W/System.err: at com.smart.mangojazan.Fragment_Payment.onResponse(Fragment_Payment.java:117)
at com.smart.mangojazan.Fragment_Payment.onResponse(Fragment_Payment.java:105)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:82)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:29)
at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:102)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
W/System.err: at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7050)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:965)
由于您期待 JSONArray，因此不要选择 StringRequest，而是使用 volley 中可用的 JsonArrayRequest。请参阅此文档：https://developer.android.com/training/volley/request
您的错误日志还表明
java.lang.String cannot be converted to JSONObject
因此我建议你试试这个：
JsonArrayRequest req = new JsonArrayRequest(Request.Method.POST, URL_PRODUCTS,
new Response.Listener<String>() {
@Override
public void onResponse(JSONArray response) {
//.............
因为您需要一个 json 数组。
您已完成所有代码，并且在发送响应之前已设置 json=["error"];
[不要忘记接受答案并在答案正确的情况下点赞或阐明（解释更多）您的问题，以便回答者可以给出更相关的答案]
<?php
require("db/Db.class.php");
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getMainCategory'])){
//your code
//remove below two lines from every if as it can be called commonly at last;
//header('Content-Type: application/json');
//echo json_encode($json);
}else if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getSlideShow'])){
//your code
}else if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getAllNews'])){
//your code
}else{
$json = ["error"];
}
header('Content-Type: application/json');
echo json_encode($json);
?>
我解决了这个问题，实际上它很荒谬..有一点 space
在第一个 params.put 中的 "username" 旁边，这导致了无法获取数据并导致异常的问题。即使我仔细检查了但不知道我是怎么错过的。感谢大家花时间并试图帮助我。我很感激。
@Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
//the line below was causing the exception. right side of "username " (space)
params.put("username ",user);
params.put("key",api);
params.put("getMainCategory",no);
return params;
}
我必须 POST 用户名、密钥和另一个参数才能将数据作为 JSONObject 获取并在 RecyclerView 中显示它们。我在 android 中使用 Volley Library，尝试了所有可能的方法 none，其中有帮助.. 尽管通过 Postman 进行测试似乎工作正常，并且当我 post 这三个参数时我得到了数据，但我不知道我在 android..
中遗漏了什么PHP代码：
<?php
require("db/Db.class.php");
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getMainCategory'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$catigory = $db->query("SELECT * FROM `oc_category_description`,oc_category WHERE oc_category_description.category_id = oc_category.category_id and oc_category.status = 1 and oc_category.parent_id = 0 and oc_category_description.language_id = 2");
$json = $catigory;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getSlideShow'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$slideShowId = (int)$_POST['getSlideShow'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$banderSlideShow = $db->query("SELECT * FROM `oc_banner_image` where `banner_id` = $slideShowId and language_id = 2");
$json = $banderSlideShow;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getAllNews'])){
$db = new DB();
$username = $_POST['username'];
$key = $_POST['key'];
$query = $db->query("SELECT * FROM oc_api where `username` = '$username' and `key` = '$key' limit 1 ");
if(count($query) == 0){
$json = ["error don't have permittion"];
}else{
$catigory = $db->query("SELECT * FROM `oc_blog_article`,`oc_blog_article_description` WHERE oc_blog_article_description.blog_article_id = oc_blog_article.blog_article_id and oc_blog_article.status = 1 and oc_blog_article_description.language_id = 2 order by oc_blog_article.sort_order");
$json = $catigory;
}
header('Content-Type: application/json');
echo json_encode($json);
return;
}
$json = ["error"];
header('Content-Type: application/json');
echo json_encode($json);
?>
JAVA代码：
public static final String URL_PRODUCTS = "http://vinsmartangle.net/shop/myApi/index.php";
private void loadProducts(final String user, final String api,final String no) {
StringRequest stringRequest = new StringRequest(Request.Method.POST, URL_PRODUCTS,
new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
//converting the string to json array object
JSONArray array = new JSONArray(response);
//traversing through all the object
for (int i = 0; i < array.length(); i++) {
//getting product object from json array
JSONObject category = array.getJSONObject(i);
String id = category.getString("category_id");
String name = category.getString("name");
Category data = new Category();
//adding the product to product list
data.setCategoryNo(id);
data.setCategoryName(name);
categoryList.add(data);
}
categoryAdapter = new CategoryAdapter(getActivity(),categoryList, Fragment_Payment.this);
recyclerView.setAdapter(categoryAdapter);
} catch (JSONException e) {
e.printStackTrace();
}
catch (JsonParseException e)
{
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.d(TAG, "onErrorResponse: Error ", error.getCause());
}
})
{
@Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
params.put("username ",user);
params.put("key",api);
params.put("getMainCategory",no);
return params;
}
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> headers = new HashMap<String, String>();
headers.put("Content-Type", "application/json");
return headers;
}
};
//adding our stringrequest to queue
Volley.newRequestQueue(getActivity()).add(stringRequest);
}
邮递员Screenshot:
[
{
"category_id": "20",
"language_id": "2",
"name": "رمان",
"description": "<p><br><\/p>",
"meta_title": "رمان",
"meta_description": "مثال لوصف القسم",
"meta_keyword": "",
"image": "catalog\/demo\/compaq_presario.jpg",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "1",
"status": "1",
"date_added": "2009-01-05 21:49:43",
"date_modified": "2019-07-03 01:53:35"
},
{
"category_id": "83",
"language_id": "2",
"name": "خضروات",
"description": "",
"meta_title": "خضروات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "2",
"status": "1",
"date_added": "2019-07-04 11:05:33",
"date_modified": "2019-07-05 06:16:54"
},
{
"category_id": "85",
"language_id": "2",
"name": "ورقيات",
"description": "",
"meta_title": "ورقيات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "0",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:06:41",
"date_modified": "2019-07-04 11:06:41"
},
{
"category_id": "90",
"language_id": "2",
"name": "عسل",
"description": "",
"meta_title": "عسل",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:08:56",
"date_modified": "2019-07-05 11:59:46"
},
{
"category_id": "87",
"language_id": "2",
"name": "صناديق",
"description": "",
"meta_title": "صناديق",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:07:43",
"date_modified": "2019-07-05 11:59:30"
},
{
"category_id": "57",
"language_id": "2",
"name": "فواكة موسمية",
"description": "<p><br><\/p>",
"meta_title": "فواكة موسمية",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "1",
"column": "1",
"sort_order": "3",
"status": "1",
"date_added": "2011-04-26 08:53:16",
"date_modified": "2019-07-03 01:52:47"
},
{
"category_id": "89",
"language_id": "2",
"name": "مشروبات",
"description": "",
"meta_title": "مشروبات",
"meta_description": "",
"meta_keyword": "",
"image": "",
"image_Icon": "",
"parent_id": "0",
"top": "0",
"column": "1",
"sort_order": "0",
"status": "1",
"date_added": "2019-07-04 11:08:01",
"date_modified": "2019-07-04 11:08:01"
}
]
当我 运行 应用程序时，我得到这个异常：
W/System.err: org.json.JSONException: Value error at 0 of type java.lang.String cannot be converted to JSONObject
at org.json.JSON.typeMismatch(JSON.java:101)
at org.json.JSONArray.getJSONObject(JSONArray.java:525)
W/System.err: at com.smart.mangojazan.Fragment_Payment.onResponse(Fragment_Payment.java:117)
at com.smart.mangojazan.Fragment_Payment.onResponse(Fragment_Payment.java:105)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:82)
at com.android.volley.toolbox.StringRequest.deliverResponse(StringRequest.java:29)
at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:102)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
W/System.err: at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7050)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:965)
由于您期待 JSONArray，因此不要选择 StringRequest，而是使用 volley 中可用的 JsonArrayRequest。请参阅此文档：https://developer.android.com/training/volley/request
您的错误日志还表明
java.lang.String cannot be converted to JSONObject
因此我建议你试试这个：
JsonArrayRequest req = new JsonArrayRequest(Request.Method.POST, URL_PRODUCTS,
new Response.Listener<String>() {
@Override
public void onResponse(JSONArray response) {
//.............
因为您需要一个 json 数组。
您已完成所有代码，并且在发送响应之前已设置 json=["error"];
[不要忘记接受答案并在答案正确的情况下点赞或阐明（解释更多）您的问题，以便回答者可以给出更相关的答案]
<?php
require("db/Db.class.php");
if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getMainCategory'])){
//your code
//remove below two lines from every if as it can be called commonly at last;
//header('Content-Type: application/json');
//echo json_encode($json);
}else if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getSlideShow'])){
//your code
}else if(isset($_POST['key']) && isset($_POST['username']) && isset($_POST['getAllNews'])){
//your code
}else{
$json = ["error"];
}
header('Content-Type: application/json');
echo json_encode($json);
?>
我解决了这个问题，实际上它很荒谬..有一点 space 在第一个 params.put 中的 "username" 旁边，这导致了无法获取数据并导致异常的问题。即使我仔细检查了但不知道我是怎么错过的。感谢大家花时间并试图帮助我。我很感激。
@Override
protected Map<String,String> getParams(){
Map<String,String> params = new HashMap<String, String>();
//the line below was causing the exception. right side of "username " (space)
params.put("username ",user);
params.put("key",api);
params.put("getMainCategory",no);
return params;
}