【发布时间】：2016-10-02 16:53:46
【问题描述】：
当我运行 php 脚本时它返回异常。 这是我的java类
public class ShowAllQuestions extends ListActivity {
int cntChoice;
ArrayList<String> selected;
Button getChoice;
// Progress Dialog
private ProgressDialog pDialog;
public static String mode;
private static final String CONNECTION_FAILED_MSG = "connection";
private ArrayList<String> nameList = new ArrayList<String>();
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
String id;
ArrayList personList;
// url to get all products list
private static String url_all_products = "http://www.rpscadda.com/QuizAPP/getallmcq.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_Person = "person";
private static final String TAG_PID = "id";
private static final String TAG_NAME = "fname";
private static final String TAG_RESULT = "result";
// products JSONArray
JSONArray person = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.all_questions);
personList = new ArrayList<HashMap<String, String>>();
final ListView myList=(ListView)findViewById(android.R.id.list);
getChoice=(Button) findViewById(R.id.button);
getChoice.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
selected=new ArrayList<String>();;
cntChoice = myList.getCount();
SparseBooleanArray sparseBooleanArray = myList.getCheckedItemPositions();
for(int i = 0; i < cntChoice; i++){
if(sparseBooleanArray.get(i)) {
selected.add(i, myList.getItemAtPosition(i).toString()) ;
Log.d("Message",String.valueOf(selected.get(i)));
String selectedFromList =selected.get(i);
String a[]=selectedFromList.split(" ");
Toast.makeText(getApplicationContext(), a[0], Toast.LENGTH_SHORT).show();
selected.add(i,a[0]);
Log.d("Message",a[0]);
}
}
try {
//receiving result from Connect class.
String result = new Connect().execute().get();
if (result != null) {
Log.i("Test", result);
JSONObject jsonObject = new JSONObject(result);
String response = (String) jsonObject.get("result");
if(response.equals("success")){
Toast.makeText(getApplicationContext(),"connected",Toast.LENGTH_LONG).show();
} else if(response.equals(CONNECTION_FAILED_MSG)) {
Toast.makeText(getApplicationContext(), "Couldn't connect to remote database.", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getApplicationContext(), "Something went wrong", Toast.LENGTH_SHORT).show();
}
} else {
Log.i("Test", "Result is empty");
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
}});
try {
//receiving result from Connect class.
ArrayList<String> result = new LoadAllProducts().execute().get();
if(result != null){
Log.i("BulkQuestions", "Updating");
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_multiple_choice, result);
myList.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
for(String r : result){
Log.i("BulkQuestions", r);
}
myList.setAdapter(adapter);
myList.refreshDrawableState();
}
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
public class Connect extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
BufferedReader inBuffer = null;
String result = "fail";
//sending POST request.
try {
String url="http://www.rpscadda.com/QuizAPP/deletemcq.php";
HttpClient httpClient = new DefaultHttpClient();
HttpPost request = new HttpPost(url);
for(int i=0;i<selected.size();i++) {
List<NameValuePair> postParameters = new ArrayList<NameValuePair>();
postParameters.add(new BasicNameValuePair("id", selected.get(i)));
UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(
postParameters);
request.setEntity(formEntity);
//executing request and storing result.
HttpResponse httpResponse = httpClient.execute(request);
//translating into input stream
HttpEntity httpEntity = httpResponse.getEntity();
InputStream content = httpEntity.getContent();
//reading from the buffer.
BufferedReader reader = new BufferedReader(new InputStreamReader(content, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
//storing into string.
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
result = sb.toString();
}
} catch(Exception e) {
// Do something about exceptions
result = e.getMessage();
e.printStackTrace();
} finally {
if (inBuffer != null) {
try {
inBuffer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return result; }
@Override
protected void onPostExecute(String result) {
}
}
class LoadAllProducts extends AsyncTask<String, String, ArrayList<String>> {
protected ArrayList<String> doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Products: ", json.toString());
try {
// Checking for SUCCESS TAG
String result = json.getString(TAG_RESULT);
if (result.equals("success")) {
// products found
// Getting Array of Products
person = json.getJSONArray("mcq");
// looping through All Products
for (int i = 0; i < person.length(); i++) {
JSONObject c = person.getJSONObject(i);
// Storing each json item in variable
id = c.getString("id");
String name = id +" "+c.getString("question");
nameList.add(name);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_PID, id);
map.put(TAG_NAME, name);
Log.i("BulkQuestions", name);
// adding HashList to ArrayList
personList.add(map);
}
} else { Log.i("BulkQuestions", "result = failed");
}
} catch (JSONException e) {
e.printStackTrace();
}
return nameList;
}
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
protected void onPostExecute(String file_url) {
}
}
}
这是我的 php 代码
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
$response['result']="connection";
die("Connection failed: " . $conn->connect_error);
}
$result = $conn->query("SELECT * FROM mcq");
$num_rows = $result->num_rows;
if($num_rows > 0){
// looping through all results
// products node
$response["mcq"] = array();
while ($row = $result->fetch_assoc()) {
// print_r($row);
// temp user array
$mcq= array();
$mcq["id"] = $row["id"];
$mcq["question"] = utf8_decode($row["question"]);
$mcq["op1"] = utf8_decode($row["op1"]);
$mcq["op2"] = utf8_decode($row["op2"]);
$mcq["op3"] = utf8_decode($row["op3"]);
$mcq["op4"] = utf8_decode($row["op4"]);
$mcq["correct"] = utf8_decode($row["correct"]);
$mcq["explanation"] = utf8_decode($row["explanation"]);
$mcq["maincat"] = $row["mainCategory"];
$mcq["subcat"] = $row["subcategory"];
$response["mcq"][] = $mcq;
}
$response['result']= "success";
} else {
// echo "Error: " . $sql . "<br>" . $conn->error;
$response['result']= "failed";
}
$conn->close();
// echoing JSON response
echo json_encode($response);?>
我的 Logcat 错误 [LogcatError][1] [1]：http://i.stack.imgur.com/M7BSb.png
当我在表中/从表中插入/检索短字符串时，我的代码运行良好，而如果我插入长字符串，它运行良好，尽管它在检索时出现此异常。
我是一个 php 初学者，并在 stackoverflow 上发布了我的第一个问题，非常抱歉描述不佳。
【问题讨论】：
-
getAllMcq.php 在浏览器上加载时也会返回 null。