conversion from NSMutableArray of NSData to NSMutableArray of NSString? - ios

my requirement is to convert the NSMutualArray of NSData into NSMutualArray of NSString, Is there any method or function which directly works for above condition, or we have to deal with individual element of each array?
My code:
for (int i = 0; i < [newTutorials count]; i++)
{
// mutableArray[i] = [[NSString alloc] initWithData:newTutorials[i] encoding:NSUTF8StringEncoding];
NSLog(#"url: %#: ",newTutorials[i]);
}
NSLog(#"%#",mutableArray);

I am not aware of anyway besides visiting each element, like:
NSMutableArray *mutableArray; // your array of objects
for (int i = 0; i < [mutableArray count]; i++)
mutableArray[i] = [[NSString alloc] initWithData:mutableArray[i] encoding:NSUTF8StringEncoding];

Answer by Firo is correct. Only change required is the syntax used to set/replaced object in NSMutableArray.
Correct syntax is :
[yourMutableArray replaceObjectAtIndex:i withObject:
[[NSString alloc] initWithData:[yourMutableArray objectAtIndex:i] encoding:NSASCIIStringEncoding];

Related

nsmutableArray replacing element with last added object

After adding new element in mutableArray previously added element(Fetched from dictionary) is also replace with newly added element.
for (int i = 0; i < [_ContentArray count]; i++){
if ([[[_ContentArray objectAtIndex:i]objectForKey:#"type"] isEqualToString:#"video"]) {
NSString *videoUrl = [[_ContentArray objectAtIndex:i]objectForKey:#"url"];
NSString *videoName = [[_ContentArray objectAtIndex:i]objectForKey:#"title"];
[_videoContentDict setValue:videoUrl forKey:#"url"];
[_videoContentDict setValue:videoName forKey:#"title"];
[_videoArray addObject:_videoContentDict];
NSLog(#"%#%%",_videoArray);
}
}
HERE -
_videoContentDict is an mutableDictionary
_videoArray is an mutableArray
I think you get each time old object with new object in to the NSMutableArray. because you are allocated NSMutableDictionary outside the for loop.
So make your NSMutableDictionary alloc init in side the for loop like following code:
for (int i = 0; i < [_ContentArray count]; i++){
if ([[[_ContentArray objectAtIndex:i]objectForKey:#"type"] isEqualToString:#"video"]) {
_videoContentDict = [[NSMutableDictionary alloc]init];
NSString *videoUrl = [[_ContentArray objectAtIndex:i]objectForKey:#"url"];
NSString *videoName = [[_ContentArray objectAtIndex:i]objectForKey:#"title"];
[_videoContentDict setValue:videoUrl forKey:#"url"];
[_videoContentDict setValue:videoName forKey:#"title"];
[_videoArray addObject:_videoContentDict];
NSLog(#"%#%%",_videoArray);
}
}

Unable to retrieve the data from Dictionary

In my project I am getting response from the server in the form
response:
<JKArray 0x7fa2e09036b0>(
{
id = 23;
name = "Name1";
},
{
id = 24;
name = "Name2";
}
)
From this response array i am retrieving the objects at different indexes and then adding them in a mutableArray and then into a contactsDictionary.
self.contactsDictionary = [[NSMutableDictionary alloc] init];
for(int i=0 ; i < [response count] ; i++)
{
NSMutableArray *mutableArray=[[NSMutableArray alloc] init];
[mutableArray addObject:[response objectAtIndex:i]];
[self.contactsDictionary setObject:mutableArray forKey:[NSString stringWithFormat:#"%i",i]];
}
I want to retrieve data for Key #"name" from the contactsDictionary at some other location in the project. So how to do it.
Thanks in advance....
this is the wrong way like you are setting your contactsDictionary.
replace below line
[self.contactsDictionary setObject:mutableArray forKey:[NSString stringWithFormat:#"%i",i]];
with
[self.contactsDictionary setObject:[mutableArray objectAtIndex :i] forKey:[NSString stringWithFormat:#"%i",i]];
becuase everytime your array have new objects so your contacts dictionary's first value have one object then second value have two object. so you shouldn't do that.
now, if you want to retrieve name then call like
NSString *name = [[self.contactsDictionary objectForKey : #"1"]valueForKey : #"name"];
avoid syntax mistake if any because have typed ans here.
Update as per comment:
just take one mutablearray for exa,
NSMutableArray *arr = [[NSMutableArray alloc]init];
[arr addObject : name]; //add name string like this
hope this will help :)
Aloha from your respond I can give you answer Belo like that according to you response.
for(int i=0;i<[arrRes count];i++);
{
NSString *strId = [NSString stringWithFormat:#"%#",[[arrRes obectAtIndex:i]objectForKey:#"id"]];
NSString *StrName = [NSString stringWithFormat:#"%#",[[arrRes objectAtIndex:i]objectForKey:#"name"]];
NSLog(#"The ID is -%#",strId);
NSLog(#"The NAME is - %#",strName);
}

Trying to create an array of dictionaries, keep getting the same dictionary repeated in the array

I'm trying to use NSData to pull information out of a text file, and then load it into a dictionary.
First I create a string of the text file, and load each record into an array.
Then I break apart the each record into individual data elements.
The problem I'm having is that when the dictionary is fully populated, I then use addObject to load it into the array, which it does do successfully. The problem is that when the next loop creates a new dictionary, the same dictionary gets loaded into the array, and I end up an array of all the same dictionaries, instead of multiple different dictionary objects.
I'm guessing there is some simple mistake I'm making that is causing this error. Any help would be appreciated.
NSString *clientListFile = [NSURL URLWithString: #"/textfile"];
NSData *clientListDataFile = [NSData dataWithContentsOfFile:clientListFile];
NSString *clientListString = [[NSString alloc]initWithBytes:[clientListDataFile bytes] length:[clientListDataFile length] encoding:NSUTF8StringEncoding];
NSString *returnDelimiter = #"\n";
NSString *commaDelimiter = #",";
NSString *exclamationDelimiter = #"!";
NSArray *keysAndObjects = [[NSArray alloc]init];
NSMutableDictionary *clientList = [[NSMutableDictionary alloc]init];
NSMutableArray *clientListOfDictionaries = [[NSMutableArray alloc]init];
NSArray *sentenceArray = [clientListString componentsSeparatedByString:returnDelimiter];
for (int i = 0; i < [sentenceArray count]; i=i+1) {
[clientList removeAllObjects]; //to start with a fresh dictionary for the next iteration
NSString *recordSentence = [sentenceArray objectAtIndex:i];
NSArray *attributes = [recordSentence componentsSeparatedByString:commaDelimiter];
for (int j = 0; j < [attributes count]; j = j+1) {
NSString *pairsOfItems = [attributes objectAtIndex:j];
//a small arry, of only two objects, the first is the key, the second is the object
keysAndObjects = [pairsOfItems componentsSeparatedByString:exclamationDelimiter];
[clientList setObject:[keysAndObjects lastObject] forKey:[keysAndObjects firstObject]];
}
[clientListOfDictionaries addObject:clientList];
}
When I used NSLog to see what's in the dictionary, I mulitple objects of the same dictionary repeated, even though up earlier in the iteration, I can see that the code is creating separate and unique dictionaries.
Instead of this line
[clientListOfDictionaries addObject:clientList];
you can have
[clientListOfDictionaries addObject:[[NSArray alloc] initWithArray:clientList];
That way you will be adding new arrays to clientListOfDictionaries instead of the same one.
Move this line:
NSMutableDictionary *clientList = [[NSMutableDictionary alloc]init];
to just after the first for loop line and then delete the line:
[clientList removeAllObjects];
It's important to create a new dictionary for each iteration.
You should also delete the following line:
NSArray *keysAndObjects = [[NSArray alloc]init];
and change:
keysAndObjects = [pairsOfItems componentsSeparatedByString:exclamationDelimiter];
to:
NSArray *keysAndObjects = [pairsOfItems componentsSeparatedByString:exclamationDelimiter];
You are allocated and initialising your clientList dictionary outside of the for loop, so you only have one dictionary, which you are storing in your array multiple times. Adding the dictionary to the array does not copy it, it merely adds a pointer to the object.
you need to move
NSMutableDictionary *clientList = [[NSMutableDictionary alloc]init];
inside your first for loop in place of
[clientList removeAllObjects];
Also, componentsSeparatedByString: returns an NSArray, so you don't need to allocate and initialise one. You can simply define the variable -
NSArray *keysAndObjects;
Because you're using the same clientList variable for each iteration of the loop. You need to create a whole new dictionary object each time.
Try this modified code:
NSData *clientListDataFile = [NSData dataWithContentsOfFile:clientListFile];
NSString *clientListString = [[NSString alloc]initWithBytes:[clientListDataFile bytes] length:[clientListDataFile length] encoding:NSUTF8StringEncoding];
NSString *returnDelimiter = #"\n";
NSString *commaDelimiter = #",";
NSString *exclamationDelimiter = #"!";
NSArray *keysAndObjects = nil;
NSMutableArray *clientListOfDictionaries = [[NSMutableArray alloc] init];
NSArray *sentenceArray = [clientListString componentsSeparatedByString:returnDelimiter];
for (NSUInteger i = 0; i < [sentenceArray count]; ++i) {
NSMutableDictionary *clientList = [[NSMutableDictionary alloc] init]; //to start with a fresh dictionary for the next iteration
NSString *recordSentence = [sentenceArray objectAtIndex:i];
NSArray *attributes = [recordSentence componentsSeparatedByString:commaDelimiter];
for (NSUInteger j = 0; j < [attributes count]; ++j) {
NSString *pairsOfItems = [attributes objectAtIndex:j];
//a small arry, of only two objects, the first is the key, the second is the object
keysAndObjects = [pairsOfItems componentsSeparatedByString:exclamationDelimiter];
[clientList setObject:[keysAndObjects lastObject] forKey:[keysAndObjects firstObject]];
}
[clientListOfDictionaries addObject:clientList];
}
An alternate option, though likely less efficient, is to to change the line:
[clientListOfDictionaries addObject:clientList];
to
[clientListOfDictionaries addObject:[clientList copy]];
That lets you keep using the same clientList variable, since you're adding a copy of it to the clientListOfDictionaries array. I just point that out because it might help you understand what's going on.
Also, note that I changed this line for you:
NSArray *keysAndObjects = [[NSArray alloc]init];
to
NSArray *keysAndObjects = nil;
Because it's just a pointer that is set by your call to componentsSeparatedByString, you don't need to allocate an array for it. That array will just vanish in your first iteration of the loop.
Should be added the new dictionary to array. Otherwise it will not add to an array. Every object in array have same dictionary mapping. So it will give you the same dictionary value. Create new dictionary for every object and add to array.
for (int i = 0; i < [sentenceArray count]; i=i+1) {
NSMutableDictionary *clientList = [[NSMutableDictionary alloc]init];
NSString *recordSentence = [sentenceArray objectAtIndex:i];
NSArray *attributes = [recordSentence componentsSeparatedByString:commaDelimiter];
for (int j = 0; j < [attributes count]; j = j+1) {
NSString *pairsOfItems = [attributes objectAtIndex:j];
//a small arry, of only two objects, the first is the key, the second is the object
NSArray *keysAndObjects = [pairsOfItems componentsSeparatedByString:exclamationDelimiter];
[clientList setObject:[keysAndObjects lastObject] forKey:[keysAndObjects firstObject]];
}
[clientListOfDictionaries addObject:clientList];
}

How convert string utf-8?

i've an NSString like this:
NSString *word = #"119,111,114,100"
So, what i want to do is to convert this NSString to word
So the question is, in which way can i convert a string to a word?
// I have added some values to your sample input :-)
NSString *word = #"119,111,114,100,32,240,159,145,141";
// Separate components into array:
NSArray *array = [word componentsSeparatedByString:#","];
// Create NSData containing the bytes:
NSMutableData *data = [[NSMutableData alloc] initWithLength:[array count]];
uint8_t *bytes = [data mutableBytes];
for (NSUInteger i = 0; i < [array count]; i++) {
bytes[i] = [array[i] intValue];
}
// Convert to NSString (interpreting the bytes as UTF-8):
NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(#"%#", str);
Output:
word 👍
Try this:
NSString *word = #"119,111,114,100";
NSArray *array=[word componentsSeparatedByString:#","];
for (NSString *string in array) {
char character=[string integerValue];
NSLog(#"%c",character);
}
Output:
w
o
r
d
libicu it's an UTF8 library that supports a conversion from an array of bytes as stated here.
The thing is, it offers Java, C or C++ APIs, not obj-c.

Converting an NSArray component into an integer or decimal number

I have a case where the data read from the CSV file in the app has to be converted into an integer, has to be plotted later. Currently it doesn't recognize when the data is saved as
int i=[[rows objectAtIndex:0] componentsSeparatedByString:#","];
This is the implemented code.
-(void)connection :(NSURLConnection *) connection didReceiveData:(NSData *)data{
[self serverConnect];
response = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
//NSLog(response);
NSString *stripped1 = [response stringByReplacingOccurrencesOfString:#"\r" withString:#""];
NSArray *rows = [stripped1 componentsSeparatedByString:#"\n"];
NSArray *components;
for (int i=0;i<[rows count]; i++) {
if(i == 0 || [[rows objectAtIndex:i] isEqualToString:#""]){
continue;
}
components = [[rows objectAtIndex:i] componentsSeparatedByString:#","];
NSLog(#"data1:%# data2:%# data3:%#", [components objectAtIndex:0] ,[components objectAtIndex:1],[components objectAtIndex:2]);
}
data1, data2 and data3 are supposed to be integers.
Thanks a lot.
componentsSeparatedByString returns substrings, or instances of NSString.
components = [[rows objectAtIndex:i] componentsSeparatedByString:#","];
You just need to take each member of 'components' and get it's intValue, like so:
int myInt = [[components objectAtIndex:n] intValue];
NSArray and NSMutableArray can only contains objects. So get the integer value from it, use [object intValue]. If you need to add an integer to an array, create a NSNumber object from the integer and insert it. I know Rayfleck answered your question and i just want to point out the way how array works in iOS. Hope this helps.

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