I have a NSWebView in which there is loaded XML data. I cannot get it with stringByEvaluatingJavaScriptFromString because JavaScript doesn't want to work with XML. How the hell am I supposed to get it? Why is it so annoying difficult to do something so simple? Creating XML from URL won't work.
How do I get XML from NSWebView into a NSString?
Do you need to use the WebView? I'd suggest just grabbing the data by itself:
NSString *content = [NSString stringWithContentsOfURL:[NSURL URLWithString:#"example.com"]];
I've worked it out myself. Thing is that you have to take the xml from WebFrame and not from WebView. You can then convert the data into a string or whatever you need.
NSData *xmlData = [[myWebView mainFrame] dataSource] data];
Related
Is there a way I can NSLog JSON response of NSData in JSONformat?
NSLog(#"JSON NSString: %#" ,jsonData);
In this post they are printing NSDictionary,I can convert it to NSDictionary. and this solution returns (null).
How can I NSLog in JSON format?
• What's wrong:
jsonData (as you gave) IS NOT a hexData representing a JSON.
• Quick hack (not viable solution!) to get your JSON to use in your site CodeBeautify:
NSDictionary *dictFromData = [NSKeyedUnarchiver unarchiveObjectWithData:jsonData];
NSData *realJSONData = [NSJSONSerialization dataWithJSONObject:dictFromData options:0 error:nil];
NSString *strFINAL = [[NSString alloc] initWithData:realJSONData encoding:NSUTF8StringEncoding];
NSLog(#"StrFINAL: %#", strFINAL);
Note: Yeah, I bypassed the error parameters, and we shouldn't. With
NSJSONWritingPrettyPrinted instead of 0 in options: parameter, you have a result almost similar to the one of CodeBeautify.
• How did I get there:
Firt, I copy/paste your bump string of NSData with this answer.
That way, I got jsonData as you got.
Then, I tried simply what it should be given your informations:
NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingAllowFragments error:&errorJSON];
Which didn't work giving the error:
Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be
completed. (Cocoa error 3840.)" (Invalid value around character 0.)
UserInfo=0x17598540 {NSDebugDescription=Invalid value around character
0.}
But with NSDictionary *dictWithData = [NSKeyedUnarchiver unarchiveObjectWithData:jsonData];, I managed to get the real NSDictionary. But NSKeyedArchiver/NSKeyedUnarchiver are doing something "equivalent" to NSJSONSerialization: it serializes, transforming a NSObject into NSData (and vice-versa). But more powerful: for any kind of object that are NSCoding compliant. Here, since it's originally from a JSON (only NSString, NSNumber, NSArray and NSDictionary objects, and not a custom one), it's working without any more code.
Did you for instance tried to save it into NSUserDefaults and it's not a .plist either (that was also one on my tries, I saved jsonData into memory, and used dictionaryWithContentsOfFile: giving me weird answer, but a important one in the bump of it: ""$class" = "{value = 23}";" which lead me to NSKeyArchiver/NSKeyUnarchiver). I don't know what you did exactly.
• Conclusion:
So clearly, somewhere, you mixed stuff found on the web. You need to rework that. You can't let it like this. There is issue in your code elsewhere. Where did you get jsonData from? What did you do with it?
Code:
NSLog("Formatted JSON : %#" ,[[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding]);
There are different situations. If parsing the JSON data was fine, then you just want to log the result (dictionary or array). If parsing the JSON data failed, and you suspect there is something wrong with the JSON data, then you convert the JSON data to an NSString and log that. And finally, if either conversion to NSString failed, or you look at the NSString and can't find what's wrong with it, then you log the NSData itself to be able to see the bytes. That's useful if someone managed to put control characters or some other nonsense into your JSON data.
The best is to write a method (warning! not for the timid! requires writing code yourself) that takes the NSData, analyses it and prints out the information that you need.
What's the reason that I can't parse a base64 string from a JSON request? when I make it a small string it works.
To clarify a little:
else if([connection isEqual:self.appearanceConnection]){
NSArray *arrayOfAppearances = [NSJSONSerialization JSONObjectWithData:[[[NSString alloc] initWithData:data
encoding:NSUTF8StringEncoding] dataUsingEncoding:NSUTF8StringEncoding]options:NSJSONReadingAllowFragments error:&error];
NSLog(#"het aantal appearances is: %i", arrayOfAppearances.count);
[self syncAppearances:arrayOfAppearances];
}
When I edit it to a small string, I get the response that the length of the received array is 1. If I change it again to the base 64 of the image, the length is 0.
http://cl.ly/image/470Z0X1P3K1b (image form JSON response)
The error I get on the String:
Updated answer:
You now inform us that JSONObjectWithData is reporting an error:
Unterminated string around character 62
Character 62 is the start of the logo. I'm not seeing the end of the JSON in any of your screen snapshots. It looks like it's getting cut off.
You haven't shown us how you are populating data, but it looks almost like you're using a NSURLConnection but trying to parse in didReceiveData as opposed to waiting for the full results and only invoking the the JSON parse in connectionDidFinishLoading. NSURLConnection will break a long response into several calls to didReceiveData and you have to append all of those NSData to a single NSMutableData, and only try to parse it when it's done retrieving everything.
You either need to (a) show us the code where you're loading data and/or (b) share the full JSON. Either your JSON isn't properly terminated or you're trying to parse it before the whole thing is downloaded (probably the latter).
Original answer:
I'm not sure if this is the problem, but your line that says:
NSArray *arrayOfAppearances = [NSJSONSerialization JSONObjectWithData:[[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] dataUsingEncoding:NSUTF8StringEncoding]options:NSJSONReadingAllowFragments error:&error];
should simply be:
NSArray *arrayOfAppearances = [NSJSONSerialization JSONObjectWithData:data
options:0
error:&error];
The JSONObjectWithData method takes a NSData, not a NSString.
And, if you're not getting anything returned from this method, you should examine the contents of error and see what it says.
If you're still unable to figure out what the problem is, perhaps you can share the full JSON response with us (give us a URL or upload it somewhere) and we can take a look at it.
With a big thanks to #Rob!
Here a little summary:
Create a variable NSMutableData (don't forget to initialise in the viewdidload)
In the didReceiveData, you append the data to your mutable data using [self.appearancedata appendData:data];
In the connectionDidFinishLoading you parse your JSON
Hi I saved a URL that has a path to a directory where I will be storing information, Now I want to retrieve the information but I don't know how to receive the items, I am trying to use initWithContentsOfURL but I dont know what the encoding would be?
This is how I saved the URL
//DirectoryPaths has the NSCAcheDirectory
dirPath = [[directoryPaths objectAtIndex:0] URLByAppendingPathComponent:[NSString stringWithFormat:#"photos.jpg"]];
How do I get a path to the URL now? I tried
NSString *pathToFile = [[NSString alloc] initWithContentsOfURL:dirPath
usedEncoding:nil
error:&error];
I have no clue what the encoding would be since I didnt use one to store the file?
I think you've misunderstood; initWithContentsOfURL:usedEncoding:error: loads a string from a URL. So you'd specify the encoding used for the string — UTF-8, ASCII or something like that.
To get a disk path from a URL you probably want [dirPath path]. In practice you can probably just load from the URL rather than hardcoding local disk behaviour.
Use NSUTF8StringEncoding or ASCII. It works for me. :)
I am converting the response data from a web request to an NSString in the following manner:
NSData *data = self.responseData;
if (!data) {
return nil;
}
NSStringEncoding encoding = CFStringConvertEncodingToNSStringEncoding(CFStringConvertIANACharSetNameToEncoding((__bridge CFStringRef)[self.response textEncodingName]));
NSString *responseString = [[NSString alloc] initWithData:data encoding:encoding];
However the resulting string looks like this:
"birthday":"04\/01\/1990",
"email":"some.address\u0040some.domain.com"
What I would like is
"birthday":"04/01/1990",
"email":"some.address#some.domain.com"
without the backslash escapes and unicode. What is the cleanest way to do this?
The response seems to be JSON-encoded. So simply decode the response string using a JSON library (SBJson, JsonKit etc.) to get the correct form.
You can replace (or remove) characters using NSString's stringByReplacingCharactersInRange:withString: or stringByReplacingOccurrencesOfString:withString:.
To remove (convert) unicode characters, use dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES (from this answer).
I'm sorry if the following has nothing to do with your case: Personally, I would ask myself where did that back-slashes come from in the first place. For example, for JSON, I'd know that some sort of JSON serializer on the other side escapes some characters (so the slashes are really there, in the response, and that is not a some weird bug in Cocoa). That way I'd able to tell for sure which characters I have to handle and how. Or maybe I'd use some kind of library to do that for me.
I have a Mac application that keeps it's own log file. It appends info to the file using NSString's writeToFile method. One of the things that it logs are URL's of web services that it is interacting with. To encode the URL, I'm doing this:
searchString = (NSString *)CFURLCreateStringByAddingPercentEscapes(NULL, (CFStringRef)searchString, NULL, (CFStringRef)#"!*'();:#&=+$,/?%#[]", kCFStringEncodingUTF8 );
The app then appends searchString to the rest of the URL and writes it to the log file. Now the problem is that after adding that URL encoding line, nothing seems to be getting written to the file. The program functions as expected otherwise however. Removing the line of code above results in all of the correct information being logged to the file (removing that line is not an option because searchString must be URL encoded).
Oh and I am using NSUTF8StringEncoding when writing the NSString to the file.
Thanks for any help.
EDIT: I know there's also a similar function to CFURLCreateStringByAddingPercentEscapes in NSString, but I've read that it doesn't always work. Can anyone shed some light on this if my original question cannot be answered? Thanks! (EDIT: same problem occurs when using stringByAddingPercentEscapesUsingEncoding:)
EDIT 2: Here's the code that I'm using to append messages to the log file.
+(void)logText:(NSString *)theString{
NSString *docsDirectory = [NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory,NSUserDomainMask,YES) objectAtIndex:0];
NSString *path = [docsDirectory stringByAppendingPathComponent:#"Folder/File.log"];
NSString *fileContents = [[[NSString alloc] initWithContentsOfFile:path] autorelease];
if([fileContents lengthOfBytesUsingEncoding:NSUTF8StringEncoding] >= 204800){
fileContents = #"";
}
NSString *timeStamp = [[NSDate date] description];
timeStamp = [timeStamp stringByAppendingString:#": "];
timeStamp = [timeStamp stringByAppendingString:theString];
fileContents = [fileContents stringByAppendingString:timeStamp];
fileContents = [fileContents stringByAppendingString:#"\n"];
[fileContents writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:NULL];
}
Because after almost a whole day no one else has offered any answers, I'm going to post a wild guess here: you're not accidentally using the string you want to output (with percent characters in it) as a format string are you?
That is, making the mistake of doing:
NSLog(#"In format strings you can use %# as a placeholder for an object, and %i for a plain C integer.")
Instead of:
NSLog(#"%#", #"In format strings you can use %# as a placeholder for an object, and %i for a plain C integer.");
But I'm going to be surprised if this turns out to be the cause of your problem, as it usually causes random-looking output, rather than absolutely no output. And in some cases, Xcode also gives compiler warnings about it (when I tried NSLog(myString), I got "warning: format not a string literal and no format arguments").
So don't shoot me down if this answer doesn't help. It would be easier to answer your question if you could show us more of your logging code. As for the one line you provided, I can't detect anything wrong with it.
Edit: Oops, I kind of missed that you mentioned you're using writeToFile:atomically:encoding:error: to write the string to the file, so it's even more unlikely you're accidentally treating it as a format string somewhere. But I'm going to leave this answer up for now. Again, you should really show us more of your code though ...
Edit: Regarding your question on a method in NSString that has similar percent encoding functionality, that would be stringByAddingPercentEscapesUsingEncoding:. I'm not sure what kind of problems you're thinking of when you say you've heard it doesn't always work. But one thing is that CFURLCreateStringByAddingPercentEscapes allows you to specify extra characters that don't normally have to be escaped but which you still want to be escaped, while the method of NSString doesn't allow you to specify this.