I am parsing rss using nsxmlparser and I would like to get some images from the rss...how can I do that?
so here is an example of the rss
<p><img scr = "IMGURL"></p>
how can I get the "IMGURL"
thanks,
TC
Here is a quick hack - only do this if you know the strings are not going to change position. Otherwise you risk crashing.
//for demo purposes lets say your <p><img scr = "IMGURL"></p> is a string named sourceString
//chop it up into an array like this and grab it from the arrays position
//create an array
NSArray *tempArray = [sourceString componentsSeparatedByString:#"\""];
//what this has done, it has create an array of objects from your source string separated by "
//so in your tempArray you will have two objects
// objectAtIndex 0 will be: <p><img scr = you wont need this so we can ignore it
// objectAtIndex 1 will be the string you want. it will be: IMGURL
// so now you can quickly create a string from it like this
NSString * imgURL = [[tempArray objectAtIndex:1]description];
Its a quick and dirty trick... but it works! So long as the data stays the same format. Your call!
You need to use a xml parser like XQuery. The query would be: /p/img#src
You can use a function such as:
NSString *stringForXQuery(NSXMLNode *node, NSString *query)
{
NSArray *results = [node objectsForXQuery:query constants:nil error:nil];
NSUInteger howManyResults = [results count];
if (howManyResults != 1) {
return nil;
}
return [[results objectAtIndex:0] stringValue];
}
And call it like this:
NSString *imgURL = stringForXQuery([yourxmldocument rootElement], #"/p/img#src");
Related
I'm a noob to iphone development and I'm trying to parse the JSONArray from this link. The problem is that when this code is executed it returns that my NSArray contains only 4 values instead of 80 values that jSONArray at the link contains. Am I properly converting the NSDictionary into NSArray. Any help is greatly appreciated. I'm following this tutorial here.
//parse out the json data
NSError* error;
NSDictionary* json = [NSJSONSerialization JSONObjectWithData:responseData //1
options:kNilOptions
error:&error];
NSArray* bitcoin = json; //2
NSLog(#"size of bitcoin is %lu", sizeof(bitcoin));
// 1) Get the bitcoin rate mtgoxUSD
for(int i = 0; i < sizeof(bitcoin); i++){
NSDictionary* forex = [bitcoin objectAtIndex:i];
NSString *mtgoxUSD = [forex objectForKey:#"symbol"];
NSLog(#"value against mtgoxUSD %#", mtgoxUSD);
if (mtgoxUSD==#"mtgoxUSD") {
NSString *bitcoinrate = [forex objectForKey:#"avg"];
if (bitcoinrate==#""||bitcoinrate==NULL) {
currencyBTC=1;
NSLog(#"currencyBTC: is 1");
}else{
currencyBTC=[bitcoinrate floatValue];
NSLog(#"currencyBTC: %f", currencyBTC);
}
break;
}
}
sizeof will return the size of the pointer structure in bytes, that's why you always see 4 as the value.
You should use the count method instead:
for(int i = 0; i < [bitcoin count]; i++)
"Am I properly converting the NSDictionary into NSArray"
No, not quite! JSONObjectWithData can return an array or a dictionary, depending on the JSON you're parsing. In this case, your JSON has a top-level array, so you don't need to convert it at all.
So first of all, replace your first few lines with this:
NSArray* json = [NSJSONSerialization JSONObjectWithData:responseData //1
options:kNilOptions
error:&error];
You then want to iterate through your array, but your current iteration code isn't quite right. You can use the count method that pgb suggested in another answer, or alternatively you can use the really nifty 'fast enumeration' feature of Objective-C, which looks like this:
for id item in json {
// Will iterate through all objects in the json array, accessible via item
}
This question is for manipulating NSString in xcode.
I have a XML text string that I get from the web that looks like this
<current temperature="73" day="Mon" humidity="59" windspeed="10"></current>
How can I get individual values from this string and put them in my NSString variables?
e.g.
NSString *tempStr = ??
NSString *dayStr = ??
NSString *windspeedStr = ??
First, download and include RaptureXML within your project as described on the RaptureXML project site.
For parsing the single given line, use the following snippet - your input is passed as inXmlString;
//transform string into an XML DOM
RXMLElement *rootNode = [RXMLElement elementFromXMLString:inXmlString
withEncoding:NSUTF8StringEncoding];
if (rootNode == nil || ![rootNode isValid])
{
//do something, we failed!
}
else
{
NSString *temperature = [rootNode attribute:#"temperature"];
NSString *day = [rootNode attribute:#"day"];
NSString *windspeed = [rootNode attribute:#"windspeed"];
}
The basic idea is to use the NSString method componentsSeparatedByString: to parse out the data you want. You'll probably need to do a bit more work to get it exactly right for your scenario.
NSArray* paArray1= [pstrXMLString componentsSeparatedByString:#" "];
temlStr= [[[paArray1 objectAtIndex:1] componentsSeparatedByString:#"="] objectAtIndex:1];
dayStr= [[[paArray1 objectAtIndex:2] componentsSeparatedByString:#"="] objectAtIndex:1];
windspeedStr= [[[paArray1 objectAtIndex:3] componentsSeparatedByString:#"="] objectAtIndex:1];
I'm trying to extract the weather information from here using Xpath on the iPhone. As of now it parses all the data but I'm stuck on how to extract the content and display it in a table.
This is what I have so far:
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:[ #"http://aviationweather.gov/adds/metars/?station_ids=1234&std_trans=translated&chk_metars=on&hoursStr=most+recent+only&submitmet=Submit"stringByReplacingOccurrencesOfString:#"1234" withString:self.title]]];
TFHpple * doc = [[TFHpple alloc] initWithHTMLData:data];
NSArray * elements = [doc searchWithXPathQuery:#"//table[1]//tr"];
NSLog(#"%#", elements);
TFHppleElement * element = [elements objectAtIndex:0];
[element content]; // Tag's innerHTML
[element tagName]; // "a"
[element attributes]; // NSDictionary of href, class, id, etc.
[element objectForKey:#"href"]; // Easy access to single attribute
If anybody needs to see what its outputting so far, let me know.
Thanks,
Andrew
I had the same issue I got to the point your at and didn't no where to go but I end up implementing this code. Hope it helps there is still little bits need to make it work correctly but do to the nature of the app I have developed this is all I can give you. its not much more its just the actual implementation into your code that you need really.
#import "XPathQuery.h"
NSMutableArray *weatherArray = [[NSMutableArray arrayWithArray:0]retain]; // Initilize the NSMutableArray can also be done with just an NSArray but you will have to change the populateArray method.
NSString *xPathLookupQuery = #"//table[1]//tr"; // Path in xml
nodes = PerformXMLXPathQuery(data, xPathLookupQuery); // Pass the data in that you need to search through
[self populateArray:weatherArray fromNodes:nodes]; // To populate multiple values into array.
session = [[self fetchContent:nodes] retain]; // To populate a single value and returns value.
- (void)populateArray:(NSMutableArray *)array fromNodes:(NSArray *)nodes
{
for (NSDictionary *node in nodes) {
for (id key in node) {
if ([key isEqualToString:#"nodeContent"]) {
[array addObject:[node objectForKey:key]];
}
}
}
}
You only need either the above code or below code unless you want both.
- (NSString *)fetchContent:(NSArray *)nodes
{
NSString *result = #"";
for (NSDictionary *node in nodes) {
for (id key in node) {
if([key isEqualToString:#"nodeContent"]) {
result = [node objectForKey:key];
}
}
}
return result;
}
I want to parse a JSON file in my iphone app. The problem is i can parse simple json files but i am confused how to do parsing on following type of json:
[{"123":
[{ "item_id":"222",
"image_count":"2",
"image_filetype":".jpg",
"image_url":"http:\/\/someurl.jpg",
},
{"item_id":"333",
"image_count":"2",
"image_filetype":".jpg",
"image_url":"http:\/\/someurl.jpg",
}]
}]
Can some on help me how to extract all the img_urls for "123".
Thank you.
NSString *jsonString = …;
// The top-level object is an array
NSArray *array = [jsonString JSONValue];
// The first element in the array is an object containing a name-value
// pair for the key/name "123". The value is itself an array
NSArray *itemsIn123 = [[array objectAtIndex:0] objectForKey:#"123"];
// Use Key-Value Coding to get an array of all values for the key
// image_url
NSArray *imgurls = [itemsIn123 valueForKey:#"image_url"];
Edit based on comments:
Since the top-level array may consist of several objects, each object having a single name-value pair with unknown name, you need to manually iterate over the top-level array:
NSString *jsonString = …;
NSMutableArray *imgurls = [NSMutableArray array];
// The top-level object is an array
NSArray *array = [jsonString JSONValue];
// Each element in the top-level array is an object
for (NSDictionary *outerObject in array) {
// Iterate over all values in the object. Each (single) value is an array
for (NSArray *innerArray in [outerObject allValues]) {
[imgurls addObjectsFromArray:[innerArray valueForKey:#"image_url"]];
}
}
The value for the object "123" will be an NSArray of NSDictionaries. Each of these dictionaries has a key "image_url" for the image url.
The code will depend on which JSON parsing library you use, but the basics should be the same.
First you want to take the key values like 123,112,189 so we will take the keys into an array
say the structure like [ Web { 123 {image url} 112 {image url} 189 {image url} ]
so
NSString *responseString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
SBJSON *jsonParser = [SBJSON alloc]init];
NSMutableArray *yourArray1 = [jsonParser objectWithString:responseString]copy]]autorelease;
ufArray = [[yourArray1 valueForKey:#"web"] copy];
for (NSString *s in ufArray) {
[keys addObject:[NSDictionary dictionaryWithObjectsAndKeys:s,#"keys",nil]];
}
NSLOG(#"keys :%#",keys);
// this will contain 112,123,114 etc values
initialize a NSMutableArray
finalArray = [NSMutableArray alloc]init];
for (int i = 0; i < [ufArray count]; i ++) {
yourArray1 = [ufArray valueForKey:[[keys objectAtIndex:i]valueForKey:#"keys"]];
// [keys object at indes:i] - > 123 val / next loop 112 array like that
[finalArray addObject:yourArray1];
}
[jsonParser release];
jsonParser = nil;
Hope this helps!
Well if that array was called jArray
var img_urls = [];
var jL = jArray[0][123].length;
var img_urls = [];
for(var i = 0; i < jL; i++){
img_urls[i] = jArray[0][123][i].image_url;
}
//display in console:
console.log(img_urls);
demo: http://jsfiddle.net/maniator/Vx3hu/4/
I've never used JSON before, never used iPhone before, never used Xcode before...but I would think its something along along the lines of...
//object and image for item ID 222
123: item_id(222).image_url("some_url")
or the second and following items
//hi
123: item_id(333).image_url("some_url")
However something better would be when you can extract the image without the URL by using the item ID and an image ID, so when calling the object 123, you can specify the item id and the image id, which would then output all the information you require. For instance the count, file type and the image could all be displayed.
123: item_id(222).image_id(222)
Is the data file SQL or XML? XML is usually faster! So read up on nodes.
Hope that helps.
DL.
i have to create an 2images and 3 labels by using code (cgrectmake)and i am having X location, y location, width and height all are stored in arrays(which i have retrieved from the web services)how can i create the image and labels can any one help me
You can join the elements of an array together with the NSString componentsJoinedByString class method:
NSString myString = [myNSArray componentsJoinedByString:#"x"];
where x is the characters you'd like to appear between each array element.
Edited to add
So in your newly-added code if these are the label values:
lbl = #"zero"
lbl1 = #"one"
lbl2 = #"two"
and you want to join them together with a space character then if you did this:
NSString *temp = [labelArray componentsJoinedByString:#" "];
NSLog(#"temp = %#", temp);
then this is what would be logged:
zero one two
Edited to further add
If you are instead trying to join the label values together to make xml elements then you might do something like this:
NSString *joinedElements = [labelArray componentsJoinedByString:#"</label><label>"];
NSString *temp = [NSString stringWithFormat:#"<label>%#</label>", joinedElements];
NSLog(#"temp = %#", temp);
then this is what would be logged:
<label>zero</label><label>one</label><label>two</label>
may be this is usefull to you.
NSString *str;
str = [arrayName objectAtIndex:i(Index NO)];
OK by this easily you can access object from the array. any type of object u can fetch this way only reception object type are change in left side.
Best of Luck.
Most objects have a -description method which returns a string representation of the object:
- (NSString *)description;
For example:
NSArray *array = [NSArray arrayWithObjects:#"The", #"quick", #"brown", #"fox", nil];
NSLog(#"%#", array); // prints the contents of the array out to the console.
NSString *arrayDescription = [array description]; // a string
It would help to know what you want to do with the string (how will you use the string). Also, what kind of objects do you have in the array?
In that case, Matthew's answer is one possibility. Another might be to use an NSMutableString and append the individual items, if you need control over how the string is created:
NSMutableString *string = [NSMutableString string];
if ([array count] >= 3) {
[string appendString:[array objectAtIndex:0]];
[string appendFormat:#"blah some filler text %#", [array objectAtIndex:1]];
[string appendString:[array objectAtIndex:2]];
}