Encode JSON data for URL - ios

In iOS, I want to send JSON data in URL to make service call. I tried following code snipped but Encoded URL seems wrong. Because in JSON there is a colon character (:) between key and value and comma character (,) for separation. But, i am not able to encode colon(:) as %3A and comma(,) as %2C
Code Snippet:
- (NSURL *)getEncodedUrl {
// Build dictionnary with parameters
NSString *abc = #"abc";
NSNumber *limitNumber = [NSNumber numberWithInt:2];
NSMutableDictionary *dictionnary = [NSMutableDictionary dictionary];
[dictionnary setObject:limitNumber forKey:#"limit"];
[dictionnary setObject:abc forKey:#"abc"];
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dictionnary options:0 error:&error];
if (!jsonData) {
debug("Json error %#",error);
return nil;
} else {
NSString *JSONString = [[NSString alloc] initWithBytes:[jsonData bytes] length:[jsonData length] encoding:NSUTF8StringEncoding];
debug("Json op %#",JSONString);
NSString* params = [JSONString stringByAddingPercentEscapesUsingEncoding:
NSASCIIStringEncoding];
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"http://baseUrl.com?param=#",params]];
debug("URL = %#",url);
return url;
}
}
OUTPUT:~
URL = http://baseUrl.com?param=%7B%22abc%22:%22abc%22,%22limit%22:2%7D
(Include colon and comma characters)
But I want following o/p:
http://baseUrl.com?param=%7B%22abc%22%3A%22abc%22%2C%22limit%22%3A2%7D
(No colon and comma characters)
Online Encoding-Decoding Site that I am referring as of now.
http://www.url-encode-decode.com/

you can simply use
NSString *url = #"http://baseUrl.com?param=%7B%22abc%22:%22abc%22,%22limit%22:2%7D";
NSString *encodeImgUrl = [url stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

I'd recommend that you send the JSON as POST data instead of the GET that you're using. It'd be more straightforward to package it as MIME data and any encoding you do would be easier to understand.

So you are trying to generate the query portion of a URL here. Colons are a perfectly legitimate character to include in URL queries. I wrote an article covering the intricacies of escaping URL queries in Cocoa:
http://www.mikeabdullah.net/escaping-url-queries-in-cocoa.html
Since you're keen to perform extra escaping, I suggest taking my sample code and extending it to specially ask for : and ; characters to be escaped too.

I made small mistake in API call that is why I am getting wrong result. There is no need to encode colon(:) as %3A and comma(,) as %2C.
One more thing I would like to share with you. You can use base64 string instead of encoding JSON part.

Related

How to show JSON response in iPhone using the objective c by dynamically adding " \" to the keys?

I am having a sample code which helps me to print the JSON response. In this I manually added the \ slash symbol before keys and values so it helps me to print the JSON . The code is :
NSString *jsonString = #"[{\"person\": {\"name\":\"James\",\"age\":\"24\"}},{\"person\": {\"name\":\"ray\",\"age\":\"70\"}}]";
Now the problem is once the JSON string gets longer I have to manually add the \ before every key.
Can someone help of how I can add "" before the keys as shown in the code above using some looping code?
Any help will be appreciated.
It's really not clear what you're trying to do - but maybe this will work...
Use:
- (NSString *)stringByReplacingOccurrencesOfString:(NSString *)target
withString:(NSString *)replacement;
The target will be ", and you'll need to escape it like this:
#"\""
The replacement will be \", escaped like this:
#"\\\""
So, this:
NSString *jsonString = #"[{\"person\": {\"name\":\"James\",\"age\":\"24\"}},{\"person\": {\"name\":\"ray\",\"age\":\"70\"}}]";
NSLog(#"%#", [jsonString stringByReplacingOccurrencesOfString:#"\"" withString:#"\\\""]);
will output this to the debug console:
2022-10-11 12:35:58.958881-0400 YourProj[6562:7795515] [{\"person\": {\"name\":\"James\",\"age\":\"24\"}},{\"person\": {\"name\":\"ray\",\"age\":\"70\"}}]
When receiving json from remote, it might look like this:
NSData *jsonData = [NSData dataWithContentsOfURL:url];
NSString *js = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
NSLog(#"%#", [js stringByReplacingOccurrencesOfString:#"\"" withString:#"\\\""]);

A string encoding issuse on IOS

I came across a problem with string encoding in ios development. The story is as below:
I create some values in Chinese and then create a NSDictionary for those values, the dictionary is used as parameter for network request:
- (void)createActivity
{
NSString *actionTheme = titleF.text;
NSString *actionTitle = biaotiF.text;
NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:actionTheme, #"actionTheme", actionTitle, #"actionTitle",nil];
[self networkrequest:];
}
Then some work has been done for the dictionary:
Transform the dictionary to the form of JSON as the type of NSString.
NSData* jsonData = [NSJSONSerialization dataWithJSONObject:param options:NSJSONWritingPrettyPrinted error:nil];
NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
Encoding the string , because of Chinese word in the string.
NSString *urlEncodedString = [jsonString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
At last a full url was create with the string above:
http://app.ic100.com/action/add?paramJson=%7B%22actionTheme%22%3A%22%E6%88%96%E8%80%85%E5%92%8C%E7%94%9F%E6%B4%BB%22%2C%22actionSite%22%3A%22%E5%8E%A (something like this)
I use the third party "ASIFormDataRequest" for network request, and I also set the StringEncoding:
ASIFormDataRequest *requstHttp = [[ASIFormDataRequest alloc] init];
[requstHttp setStringEncoding:NSUTF8StringEncoding];
....
All the datas has been sent to the server successfully, but when I request these data from the server and show then on the iphone. It turn to be unreadable text:
I have carefully checked all the place that I should encode or decode the string, and only utf8 is used. What`s more , for the server side , no other encoding used either. And my colleague has tested sent data from Android platform, no problem. So I think maybe I have missed some points.
Any advise?
By using the class Base64 you can encode or decode the string.
Add Base64 class in your project from HERE
see the mehode in class to encode.
Encode:
+ (NSString *)stringWithBase64EncodedString:(NSString *)string;
- (NSString *)base64EncodedString;
Decode:
- (NSString *)base64DecodedString;

How do I urlencode this NSString that contains a JSON inside it?

I have the following json string that should be sent to the backend
{
id = "MU_200255802";
keywords = (
Talk,
games,
meetup,
time,
meet,
"Time for Another Game"
);
}
So before this JSON I have the java servlet URL something like
http://....net/servletName?
How should I urlencode the json string and the url because even after trying several options, I keep getting bad url as an error back in the delegate method. What is the right way to do it/
I tried encoding using
NSString *urlStringEncoded = [[NSString stringWithString:urlString] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
and also used other encoding formats too.
Use this to create json string
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:#"Your object" options:NSJSONWritingPrettyPrinted error:&error];
NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
You can use Google Toolbox for Mac, check it out here, https://code.google.com/p/google-toolbox-for-mac/source/checkout
There are Classes named GTMNSString+HTML,GTMNSString+XML,GTMNSString+URLArguments, which contains many encoding methods for you.

iOS : decode utf8 string

I'm receiving a json data from server with some strings inside. I use SBJson https://github.com/stig/json-framework to get them.
However when I output some strings at UILabel they look like this: \u0418\u043b\u044c\u044f\u0411\u043b\u043e\u0445 (that's Cyrillic symbols)
And it's all right with latin characters
How can I decode it into normal symbols?
Some code about getting data:
NSData * data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
NSString *stringData = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSDictionary *object = [parser objectWithString:stringData error:nil];
NSString *comments = [NSString stringWithFormat:#"%#",[object valueForKey:#"comments"]];
String comments has a very special format, so I'm doing some operation like stringByTrimmingCharactersInSet ,
stringByReplacingOccurrencesOfString ,
NSArray* json_fields = [comments_modified componentsSeparatedByString: #";"];
to get a final data.
This is an example of received data after some trimming/replacing (it's NSString* comments):
"already_wow"=0;"date_created"="2012/03/1411:11:18";id=41598;name="\U0418\U043b\U044c\U044f\U0411\U043b\U043e\U0445";text="\U0438\U043d\U0442\U0435\U0440\U0435\U0441\U043d\U043e";"user_id"=1107;"user_image"="user_image/a6/6f/96/21/20111220234109510840_1107.jpg";"user_is_deleted"=0;username=IlyaBlokh;"wow_count"=0;
You see that fields text and name are encoded
If I display them on the view (at UILabel for example), they still look the same
maybe the string returned is just the unicode string representation (ascii string), that's means not returned the content encoded with utf8, to try this with NSASCIIStringEncoding to get stringData

Encrypted twitter feed

I'm developing an iOS application , that will take a twits from twitter,
I'm using the following API
https://api.twitter.com/1/statuses/user_timeline.json?include_entities=true&include_rts=true&count=2&screen_name=TareqAlSuwaidan
The problem are feed in Arabic Language ,
i.e the text feed appears like this
\u0623\u0646\u0643 \u0648\u0627\u0647\u0645
How can i get the real text (or how to encode this to get real text) ?
This is not encrypted, it is unicode. The codes 0600 - 06ff is Arabic. NSString handles unicode.
Here is an example:
NSString *string = #"\u0623\u0646\u0643 \u0648\u0627\u0647\u0645";
NSLog(#"string: '%#'", string);
NSLog output:
string: 'أنك واهم'
The only question is exactly what problem are you seeing, are you getting the Arabic text? Are you using NSJSONSerialization to deserialize the JSON? If so there should be no problem.
Here is an example with the question URL (don't use synchronous requests in production code):
NSURL *url = [NSURL URLWithString:#"https://api.twitter.com/1/statuses/user_timeline.json?include_entities=true&include_rts=true&count=2&screen_name=TareqAlSuwaidan"];
NSData *data = [NSData dataWithContentsOfURL:url];
NSError *error;
NSArray *jsonObject = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&error];
NSDictionary *object1 = [jsonObject objectAtIndex:0];
NSString *text = [object1 objectForKey:#"text"];
NSLog(#"text: '%#'", text);
NSLog output:
text: '#Naser_Albdya أيدت الثورة السورية منذ بدايتها وارجع لليوتوب واكتب( سوريا السويدان )
Those are Unicode literals. I think all that's needed is to use NSString's stringWithUTF8String: method on the string you have. That should use NSString's native Unicode handling to convert the literals to the actual characters. Example:
NSString *directFromTwitter = [twitterInterface getTweet];
// directFromTwitter contains "\u0623\u0646\u0643 \u0648\u0627\u0647\u0645"
NSString *encodedString = [NSString stringWithUTF8String:[directFromTwitter UTF8String]];
// encodedString contains "أنك واهم", or something like it
The method call inside the conversion call ([directFromTwitter UTF8String]) is to get access to the raw bytes of the string, that are used by stringWithUTF8String. I'm not exactly sure on what those code points come out to, I just relied on Python to do the conversion.

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