Php Json数组为null，而jsonobject具有该值
当检索myjson字符串时，我使用json将数据从php检索到android，当我使用Php Json数组为null，而jsonobject具有该值,php,android,arrays,Php,Android,Arrays,当检索myjson字符串时，我使用json将数据从php检索到android，当我使用 array= j.getJSONArray("result"); j有第一个数组元素，但我的数组为空。 有人能告诉我这背后的确切原因吗 public void getData() { class GetDataJSON extends AsyncTask<String, Void, String> { @Override
array= j.getJSONArray("result");
public void getData() {
class GetDataJSON extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
HttpPost httppost = new HttpPost("http://futuroitsolutions.in/php_android_api/data1.php");
// Depends on your web service
httppost.setHeader("Content-type", "application/json");
InputStream inputStream = null;
String result = null;
try {
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
inputStream = entity.getContent();
// json is UTF-8 by default
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
result = sb.toString();
} catch (Exception e) {
// Oops
} finally {
try {
if (inputStream != null) inputStream.close();
} catch (Exception squish) {
}
}
return result;
}
@Override
protected void onPostExecute(String result) {
myJSON = result;
ShowList( );
}
}
GetDataJSON g = new GetDataJSON();
g.execute();
}
public void ShowList() {
try {
String vi=myJSON;
vi=vi.replace('[',' ').replace(']',' ');
JSONObject j = new JSONObject(vi);
array= j.getJSONArray("result");
try {
for(int i=0;i<array.length();i++){
JSONObject c = array.getJSONObject(i);
id = c.getString(TAG_ID);
name = c.getString(TAG_NAME);
km = c.getString(TAG_KILOMETER);
time = c.getString(TAG_TIMING);
// get your data from jsonobject
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// String regno = c.getString(TAG_REG);
// String phone = c.getString(TAG_PHONE);
// String category = c.getString(TAG_CAT);
}
catch (JSONException e) {
e.printStackTrace();
}
TableLayout tv = (TableLayout) findViewById(R.id.table);
tv.removeAllViewsInLayout();
int flag = 1;
int c=array.length();
for (int i = 0; i < c ; i++) {
TableRow tr = new TableRow(MainActivity.this);
tr.setLayoutParams(new LayoutParams(
LayoutParams.FILL_PARENT,
LayoutParams.WRAP_CONTENT));
if (flag == 1) {
TextView b6 = new TextView(MainActivity.this);
b6.setText("Id");
b6.setTextColor(Color.BLUE);
b6.setTextSize(15);
tr.addView(b6);
TextView b19 = new TextView(MainActivity.this);
b19.setPadding(10, 0, 0, 0);
b19.setTextSize(15);
b19.setText("Task name");
b19.setTextColor(Color.BLUE);
tr.addView(b19);
TextView b29 = new TextView(MainActivity.this);
b29.setPadding(10, 0, 0, 0);
b29.setText("Timing");
b29.setTextColor(Color.BLUE);
b29.setTextSize(15);
tr.addView(b29);
tv.addView(tr);
TextView b21 = new TextView(MainActivity.this);
b29.setPadding(10, 0, 0, 0);
b29.setText("Kilometers");
b29.setTextColor(Color.BLUE);
b29.setTextSize(15);
tr.addView(b21);
tv.addView(tr);
final View vline = new View(MainActivity.this);
vline.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.FILL_PARENT, 2));
vline.setBackgroundColor(Color.BLUE);
tv.addView(vline);
flag = 0;
} else {
//JSONObject json_data = jArray.getJSONObject(i);
// Log.i("log_tag", "id: " + json_data.getInt("Id") + ", Username: " + json_data.getString("Task name") + ", No: " + json_data.getString("Kilometers"));
TextView b = new TextView(MainActivity.this);
String stime =id;
b.setText(stime);
b.setTextColor(Color.RED);
b.setTextSize(15);
tr.addView(b);
TextView b1 = new TextView(MainActivity.this);
b1.setPadding(10, 0, 0, 0);
b1.setTextSize(15);
String stime1 = name;
b1.setText(stime1);
b1.setTextColor(Color.BLACK);
tr.addView(b1);
TextView b2 = new TextView(MainActivity.this);
b2.setPadding(10, 0, 0, 0);
String stime2 = time;
b2.setText(stime2);
b2.setTextColor(Color.BLACK);
b2.setTextSize(15);
tr.addView(b2);
tv.addView(tr);
TextView b3 = new TextView(MainActivity.this);
b2.setPadding(10, 0, 0, 0);
String stime3 = km;
b2.setText(stime3);
b2.setTextColor(Color.BLACK);
b2.setTextSize(15);
tr.addView(b2);
tv.addView(tr);
final View vline1 = new View(MainActivity.this);
vline1.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.FILL_PARENT, 1));
vline1.setBackgroundColor(Color.WHITE);
tv.addView(vline1);
}
}
}
您尚未在while循环之外定义变量$rows。这就是$rows的作用域未定义的原因
<?php
include('sql.php');
mysql_query('SET CHARACTER SET utf8') ;
$rows=array();
$result = mysql_query('SELECT * FROM Location') or die(mysql_error());
while($row = mysql_fetch_assoc($result))
{
$rows[] = $row;
}
$final=array("result"=>$rows);
echo json_encode($rows);
String vi=myJSON;
JSONArray array = new JSONArray(vi);
您可以尝试以下代码：
JSONArray jsonArray = new JSONArray(vi);
for(int k = 0; k < jsonArray.length(); k++)
{
JSONObject jsonObject = jsonArray.getJSONObject(k);
jsonObject.getString("id");
jsonObject.getString("Taskname");
.............
// parse all fields like above
}
你得到的是JSONObject，而不是你说的vi中的JSONArray。如果你想要结果，你应该在php中编码$final，而不是$rows。我只编码final，但它也给出了数组null，所以只有我编码了$rows，而且当我编码时，我得到了类似于{results………[…]的json。给我你的json对象你还在这样做吗？vi=vi.替换“[”，''。替换“]'，''；如果是，请删除该行。我正在获取数组，但其长度似乎为空
String vi=myJSON;
JSONArray array = new JSONArray(vi);
JSONArray jsonArray = new JSONArray(vi);
for(int k = 0; k < jsonArray.length(); k++)
{
JSONObject jsonObject = jsonArray.getJSONObject(k);
jsonObject.getString("id");
jsonObject.getString("Taskname");
.............
// parse all fields like above
}