Android JSONException：无法将 java.lang.String 类型的值转换为 JSONObject
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JSONException: Value of type java.lang.String cannot be converted to JSONObject
提问by RCK69
I have a JSON file with 2 JSON-Arrays in it: One Array for routes and one Array for sights.
我有一个 JSON 文件，其中包含 2 个 JSON 数组：一个数组用于路线，一个数组用于景点。
A route should consist of several sights where the user gets navigated to. Unfortunately I am getting the error:
一条路线应该由用户导航到的几个景点组成。不幸的是我收到错误：
JSONException: Value of type java.lang.String cannot be converted to JSONObject
JSONException：无法将 java.lang.String 类型的值转换为 JSONObject
Here are my variables and the code that parses the JSON-File:
这是我的变量和解析 JSON 文件的代码：
private InputStream is = null;
private String json = "";
private JSONObject jObj = null;
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
// hier habe ich das JSON-File als String
json = sb.toString();
Log.i("JSON Parser", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
Log.i("JSON Parser", json);
shows me that at the beginning of the generated string there is a strange sign: 
Log.i("JSON 解析器", json); 告诉我在生成的字符串的开头有一个奇怪的符号：
but the error happens here:
但错误发生在这里：
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
04-22 14:01:05.043: E/JSON Parser(5868): Error parsing data org.json.JSONException: Value //STRANGE SIGN HERE // of type java.lang.String cannot be converted to JSONObject
04-22 14:01:05.043: E/JSON Parser(5868): 解析数据时出错 org.json.JSONException: Value //STRANGE SIGN HERE // 类型 java.lang.String 无法转换为 JSONObject
anybody has a clue on how to get rid of these signs in order to create the JSONObject?
任何人都有关于如何摆脱这些标志以创建 JSONObject 的线索？
采纳答案by Zaz Gmy
see this http://stleary.github.io/JSON-java/org/json/JSONObject.html#JSONObject-java.lang.String-
看到这个 http://stleary.github.io/JSON-java/org/json/JSONObject.html#JSONObject-java.lang.String-
JSONObject
JSON对象
public JSONObject(java.lang.String source)
throws JSONException
Construct a JSONObject from a source JSON text string. This is the most commonly used` JSONObject constructor.
从源 JSON 文本字符串构造一个 JSONObject。这是最常用的`JSONObject 构造函数。
Parameters:
source - `A string beginning with { (left brace) and ending with } (right brace).`
Throws:
JSONException - If there is a syntax error in the source string or a duplicated key.
you try to use some thing like:
您尝试使用以下内容：
new JSONObject("{your string}")
回答by khaintt
Reason is some un-wanted characters was added when you compose the String. The temp solution is
原因是在编写字符串时添加了一些不需要的字符。临时解决方案是
return new JSONObject(json.substring(json.indexOf("{"), json.lastIndexOf("}") + 1));
But try to remove hidden characters on source String.
但是尝试删除源字符串上的隐藏字符。
回答by MTurPash
Had the same problem for few days. Found a solution at last. The PHP server returned some unseen characters which you could not see in the LOG or in System.out.
有同样的问题几天了。终于找到解决办法了。PHP 服务器返回了一些您在 LOG 或 System.out 中看不到的看不见的字符。
So the solution was that i tried to substring my json String one by one and when i came to substring(3) the error went away.
所以解决方案是我尝试将我的 json String 一个一个地子串起来，当我来到 substring(3) 时，错误消失了。
BTW. i used UTF-8 encoding on both sides.
PHP side: header('Content-type=application/json; charset=utf-8');
顺便提一句。我在两边都使用了 UTF-8 编码。PHP端：header('Content-type=application/json; charset=utf-8');
JAVA side: BufferedReader reader = new BufferedReader(new InputStreamReader(is, "utf-8"), 8);
JAVA方面： BufferedReader reader = new BufferedReader(new InputStreamReader(is, "utf-8"), 8);
So try the solution one by one 1,2,3,4...! Hope it helps you guys!
所以一一尝试解决方案 1,2,3,4...！希望对大家有帮助！
try {
jObj = new JSONObject(json.substring(3));
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data [" + e.getMessage()+"] "+json);
}
回答by izbrannick
Here is UTF-8 version, with several exception handling:
这是 UTF-8 版本，有几个异常处理：
static InputStream is = null;
static JSONObject jObj = null;
static String json = null;
static HttpResponse httpResponse = null;
public JSONObject getJSONFromUrl(String url) {
// Making HTTP request
try {
HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, 10000);
HttpConnectionParams.setSoTimeout(params, 10000);
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);
HttpProtocolParams.setUseExpectContinue(params, true);
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient(params);
HttpGet httpPost = new HttpGet( url);
httpResponse = httpClient.execute( httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException ee) {
Log.i("UnsupportedEncodingException...", is.toString());
} catch (ClientProtocolException e) {
Log.i("ClientProtocolException...", is.toString());
} catch (IOException e) {
Log.i("IOException...", is.toString());
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "utf-8"), 8); //old charset iso-8859-1
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
reader.close();
json = sb.toString();
Log.i("StringBuilder...", json);
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (Exception e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
try {
jObj = new JSONObject(json.substring(json.indexOf("{"), json.lastIndexOf("}") + 1));
} catch (Exception e0) {
Log.e("JSON Parser0", "Error parsing data [" + e0.getMessage()+"] "+json);
Log.e("JSON Parser0", "Error parsing data " + e0.toString());
try {
jObj = new JSONObject(json.substring(1));
} catch (Exception e1) {
Log.e("JSON Parser1", "Error parsing data [" + e1.getMessage()+"] "+json);
Log.e("JSON Parser1", "Error parsing data " + e1.toString());
try {
jObj = new JSONObject(json.substring(2));
} catch (Exception e2) {
Log.e("JSON Parser2", "Error parsing data [" + e2.getMessage()+"] "+json);
Log.e("JSON Parser2", "Error parsing data " + e2.toString());
try {
jObj = new JSONObject(json.substring(3));
} catch (Exception e3) {
Log.e("JSON Parser3", "Error parsing data [" + e3.getMessage()+"] "+json);
Log.e("JSON Parser3", "Error parsing data " + e3.toString());
}
}
}
}
}
// return JSON String
return jObj;
}
回答by Mustafa Ferhan
This is simple way (thanks Gson)
这是简单的方法（感谢 Gson）
JsonParser parser = new JsonParser();
String retVal = parser.parse(param).getAsString();
https://gist.github.com/MustafaFerhan/25906d2be6ca109f61ce#file-evaluatejavascript-string-problem
https://gist.github.com/MustafaFerhan/25906d2be6ca109f61ce#file-evaluatejavascript-string-problem
回答by Alex Escobar
This worked for me
这对我有用
json = json.replace("\\"","'");
JSONObject jo = new JSONObject(json.substring(1,json.length()-1));
回答by Nic Raboy
I think the problem may be in the charset that you are trying to use. It is probably best to use UTF-8 instead of iso-8859-1.
我认为问题可能出在您尝试使用的字符集中。最好使用 UTF-8 而不是 iso-8859-1。
Also open whatever file is being used for your InputStream and make sure no special characters were accidentally inserted. Sometimes you have to specifically tell your editor to display hidden / special characters.
还要打开用于 InputStream 的任何文件，并确保没有意外插入特殊字符。有时您必须特别告诉您的编辑器显示隐藏/特殊字符。
回答by user4879711
return response;
After that get the response we need to parse this By:
之后得到响应，我们需要解析这个通过：
JSONObject myObj=new JSONObject(response);
On response there is no need for double quotes.
响应时不需要双引号。
回答by Jamal
I made this change and now it works for me.
我做了这个改变，现在它对我有用。
//BufferedReader reader = new BufferedReader(new InputStreamReader(is, "iso-8859-1"), 8);
BufferedReader reader = new BufferedReader(new InputStreamReader(is, HTTP.UTF_8), 8);
回答by Rasel
In my case the problem occured from phpfile.
It gave unwanted characters.That is why a json parsingproblem occured.
在我的情况下，问题出在php文件中。它给出了不需要的字符。这就是出现json parsing问题的原因。
Then I paste my php codein Notepad++and select Encode in utf-8 without BOMfrom Encodingtab and running this code-
然后我粘贴我php code的Notepad++并Encode in utf-8 without BOM从Encoding选项卡中选择并运行此代码 -
My problem gone away.
我的问题消失了。
