I have a NSMutableArray and I need to compare the content in it with a NSString..But couldn't get it ?
My array
(
{
Code=Sunday;
},
{
Code=Monday;
},
{
Code=Tuesday;
}
)
I m comparing like this :
BOOL isTheObjectThere = [array containsObject:weekday];
if([arr count]==0 && isTheObjectThere==YES)
{
//do something
}
else
{
//do something
}
Here weekday is NSString whose value=Sunday
But isTheObjectThere is returning NO..
Where Im going wrong?
see this example
NSMutableArray* array = [NSArray arrayWithObjects:#"Sunday", #"Monday", #"Tuesday", nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"SELF IN %#", array];
BOOL isTheObjectThere = [predicate evaluateWithObject:#"Sunday"];
NSLog(#"isTheObjectThere %d",isTheObjectThere);
its work fine and return isTheObjectThere 1
The array contains dictionary elements, then retrieve values of key(Code).
NSMutableArray *yourArray = [[NSMutableArray alloc] init];
for (NSDictionary *dict in array) {
[yourArray addObject:[dict valueForKey:#"Code"]];
}
BOOL isTheObjectThere = [yourArray containsObject:#"Sunday"];
BOOL isTheObjectThere = [array containsObject:weekday];
will not work, better try the following method.
NSMutableArray* inputArray = [NSArray arrayWithObjects:#"Sunday", #"Monday", #"Tuesday", nil];
for (NSString* item in inputArray)
{
if ([item rangeOfString:#"Sunday"].location != NSNotFound)
{
//do something
}
else
{
//do something;
}
}
NSString *yourString = #"Monday";
for (NSString* item in inputArray){
if ([yourString rangeOfString:item].location != NSNotFound)
//Do something;
else
// Do the other Thing;
}
Related
I have the array like:
(
{
id=1;
Title="AAAA";
period_id=1;
},
{
id=2;
Title="BBBB";
period_id=2;
},
{
id=3;
Title="CCCC";
period_id=2;
},
{
id=4;
Title="DDDD";
period_id=2;
},
{
id=5;
Title="EEEE";
period_id=3;
},
)
Question: How can i know that Period_id=2 is multiple times in the array?
Help me solve this.
Thank you,
There are lots of ways to do so, Some of them are here ..
A:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"period_id == %#", #"2"];
NSArray *newArray = [array filteredArrayUsingPredicate:predicate];
NSLog(#"%d", [newArray count]);
B:
NSMutableArray *newArray = [[NSMutableArray alloc] init];
for (id obj in array)
{
if([obj[#"period_id"] isEqualToString:#"2"]){
[newArray addObject:obj];
}
}
NSLog(#"%d", [newArray count]);
C:
NSArray *allIds = [array valueForKey:#"period_id"];
NSCountedSet *set = [[NSCountedSet alloc] initWithArray:allIds];
for (id item in set)
{
NSLog(#"period_id=%#, Count=%d", item,[set countForObject:item]);
}
D:
NSArray *allIds = [array valueForKey:#"period_id"];
__block NSMutableArray *newArray = [[NSMutableArray alloc] init];
NSString *valueToCheck = #"2";
[allIds enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
if([obj isEqualToString:valueToCheck])
[newArray addObject:obj];
}];
NSLog(#"%d", [newArray count]);
E:
NSIndexSet *indexes = [array indexesOfObjectsPassingTest:^(id obj, NSUInteger idx, BOOL *stop) {
return [[obj objectForKey:#"period_id"] isEqualToString:#"2"];
}];
NSArray *newArray = [array objectsAtIndexes:indexes];
NSLog(#"%d", [newArray count]);
try like this,
NSIndexSet *indices = [questionSections indexesOfObjectsPassingTest:^(id obj, NSUInteger idx, BOOL *stop) {
return [[obj objectForKey:#"period_id"] isEqualToString:#"2"];
}];
NSArray *filtered = [questionSections objectsAtIndexes:indices];
NSLog(#"duplictae:%d\n %#",[indices count],filtered);
O/P:-
duplicate: 3
(
{
name = bbbb;
"period_id" = 2;
},
{
name = ccccc;
"period_id" = 2;
},
{
name = ddddd;
"period_id" = 2;
}
)
if the array is sorted, as it seems at your case, just check if the next item has the same value as this one
for(int i = 0; i < array.size() - 1; i++) {
if (array[i].id == array[i + 1].id) {
// Duplicate
}
}
if you just want to know about id = 2
int idCount = 0;
for(int i = 0; i < array.size() - 1; i++) {
if (array[i].id == 2) {
idCount++;
}
}
if you also want to know the location
int idCount = 0;
int idarr[array.size()];
for(int i = 0; i < array.size() - 1; i++) {
if (array[i].id == 2) {
idarr[idCount++] = i;
}
}
I think this is a JSON response from what I gather. Yes you can get the period_id. Add all the period_id's in an NSMutableArray.
Then simply search for the period_id from within this array for the values of the period_id to be same . You will get the index on which the period_id's are same.
NSSet *uniqueElements = [NSSet setWithArray:myArray];
for(id element in uniqueElements) {
// iterate here
}
You could also use NSPredicate to check duplicate.
Try this Example:
NSPredicate *testPredicate = [NSPredicate predicateWithFormat:#"period_id.intValue == %d",value];
NSMutableArray *data = [[NSMutableArray alloc] init];
NSArray *testArray= [yourArray filteredArrayUsingPredicate:testPredicate];
NSLog(#"duplicate:%d",[testArray count]);
Right now i have a dictionary like this, it's just a example, i got A to Z:
(
{
id = 13;
name = "Roll";
firstLetter = R;
},
{
id = 14;
name = "Scroll";
firstLetter = S;
},
{
id = 16;
name = "Rock";
firstLetter = R;
},
{
id = 17;
name = "Start";
firstLetter = S;
}
)
I want to extract the dict has the same firstLetter and combine these into a NSArray object. The expected results like this:
R array:
(
{
id = 13;
name = "Roll";
firstLetter = R;
},
{
id = 16;
name = "Rock";
firstLetter = R;
}
)
and S array:
(
{
id = 14;
name = "Scroll";
firstLetter = S;
},
{
id = 17;
name = "Start";
firstLetter = S;
}
)
How to do that?
I believe the better method would be the one suggested by Saohooou
But it can be optimised as
NSArray *array = #[#{#"id": #13,#"name":#"Roll",#"firstLetter":#"R"},
#{#"id": #14,#"name":#"Scroll",#"firstLetter":#"S"},
#{#"id": #15,#"name":#"Rock",#"firstLetter":#"R"},
#{#"id": #16,#"name":#"Start",#"firstLetter":#"S"}];
NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
[array enumerateObjectsUsingBlock:^(NSDictionary *dict, NSUInteger idx, BOOL *stop) {
NSString *key = dict[#"firstLetter"];
NSMutableArray *tempArray = dictionary[key];
if (!tempArray) {
tempArray = [NSMutableArray array];
}
[tempArray addObject:dict];
dictionary[key] = tempArray;
}];
NSLog(#"%#",dictionary);
NSMutableDictionay *dic = [NSMutableDictionay dictionay];
for ( YourObject *obj in yourDic.allValues )
{
NSMutableArray *dateArray = dic[obj.firstLetter];
if ( !dateArray )
{
dateArray = [NSMutableArray array];
[dic setObject:dateArray forKey:obj.firstLetter];
}
[dateArray addObject:obj];
}
so dic is what you want
I assume you organized the dict as an NSArray.
NSMutableDictionary* result = [NSMutableDictionary dictionary]; // NSDictionary of NSArray
for (id entry in dict) {
NSString* firstLetter = [entry firstLetter];
// Find the group of firstLetter
NSMutableArray* group = result[firstLetter];
if (group == nil) {
// No such group --> create new a new one and add it to the result
group = [NSMutableArray array];
result[firstLetter] = group;
}
// Either group has existed, or has been just created
// Add the entry to it
[group addObject: entry];
}
result holds what you want.
try this
NSString *currentStr;
//this int is to detect currentStr
NSInteger i;
NSMutableArray* R_Array = [[NSMutableArray alloc] init];
NSMutableArray* S_Array = [[NSMutableArray alloc] init];
for (NSDictionary *myDict in MyDictArray){
NSString *tempStr = [myDict objectForKey:#"firstLetter"];
if(currentStr = nil && [currentStr isEqualToString:""]){
currentStr = tempStr;
if([currentStr isEqualToString:"R"] ){
[R_Array addObject:myDict];
i = 0;
}else{
[S_Array addObject:myDict];
i = 1;
}
}else{
if([currentStr isEqualToString:tempStr]){
(i=0)?[R_Array addObject:myDict]:[S_Array addObject:myDict];
}else{
(i=0)?[R_Array addObject:myDict]:[S_Array addObject:myDict];
}
}
}
Base on your dictionaries. There are only two type, so i just created two array and use if-else for solving the problem. if there are multy values, you can try switch-case to do it.
Lets do this
NSMutaleDictionary * speDict = [[NSMutableDictionary alloc] init];
for(i=0;i<26;i++){
switch (i){
case 0:
[speDict setObject:[NSMutableArray alloc] init] forKey:#"A"];
break;
case 1:
[speDict setObject:[NSMutableArray alloc] init] forKey:#"B"];
break;
Case 2:
[speDict setObject:[NSMutableArray alloc] init] forKey:#"C"];
break;
...........
Case 25:
[speDict setObject:[NSMutableArray alloc] init] forKey:#"Z"];
break;
}
}
for (NSDictionary *myDict in MyDictArray){
NSString *tempStr = [myDict objectForKey:#"firstLetter"];
switch (tempStr)
case A:
[self addToMySpeDictArrayWithObject:myDict andStr:temStr];
break;
case B:
[self addToMySpeDictArrayWithObject:myDict andStr:temStr];
break;
Case C:
[self addToMySpeDictArrayWithObject:myDict andStr:temStr];
break;
...........
Case Z:
[self addToMySpeDictArrayWithObject:myDict andStr:temStr];
break;
}
-(void)addToMySpeDictArrayWithObject:(NSDictionary*)_dict andStr:(NString*)_str
{
NSMutableArray *tempArray = [speDict objectForKey:_str];
[tempArray addObject:_dict];
}
then the speDict is like
A:
//all firstletter is A
myDict
myDict
myDict
B:
//all firstletter is B
myDict
myDict
.......
First of all the sample you've provided is an array of dicts (not a dict as the question notes). Now, the easiest way to query this array is by using an NSPredicate. Something like this perhaps:
NSArray *objects = ...; // The array with dicts
NSString *letter = #"S"; // The letter we want to pull out
NSPredicate *p = [NSPredicate predicateWithFormat:#"firstLetter == %#", letter];
NSArray *s = [objects filteredArrayUsingPredicate:p]; // All the 'S' dicts
If for some reason you need to group all of your objects without having to ask for a specific letter each time, you could try something like this:
// Grab all available firstLetters
NSSet *letters = [NSSet setWithArray:[objects valueForKey:#"firstLetter"]];
for (NSString *letter in letters)
{
NSPredicate *p = [NSPredicate predicateWithFormat:#"firstLetter == %#", letter];
NSArray *x = [objects filteredArrayUsingPredicate:p];
// Do something with 'x'
// For example append it on a mutable array, or set it as the object
// for the key 'letter' on a mutable dict
}
And of course you could further optimize this approach by implementing a method for filtering the array based on a letter. I hope that this makes sense.
The question sounds weird but I'm getting an array of dictionaries as parsed result.
Something like this:
parsed content: (
{
"name" = "John";
"lastname" = "Doe";
"foo" = "bar";
}
What would be the suggestion for best way to create an array of values??
Like this?
- (void)flattenDictionary:(NSDictionary *)d intoKeys:(NSMutableArray *)keys andValues:(NSMutableArray *)values {
for (id key in [d allKeys]) {
[keys addObject:key];
[values addObject:[d valueForKey:key]];
}
}
- (void)flattenDictionaries:(NSArray *)arrayOfDictionaries {
NSMutableArray *keys = [NSMutableArray array];
NSMutableArray *values = [NSMutableArray array];
for (NSDictionary *d in arrayOfDictionaries) {
[self flattenDictionary intoKeys:keys andValues:values];
}
NSLog(#"now we have these values %#", values);
NSLog(#"corresponding to these keys %#", keys);
}
You can get the values with:
NSArray *values = dictionary.allValues;
Or, loop through it:
[dictionary enumerateKeysAndObjectsUsingBlock:^(id key, id object, BOOL *stop) {
NSLog(#"%# = %#", key, object);
}];
To do that loop through them and create an array.
Now I'm trying the following and it works.
- (void)findDictionaryWithValueForKey:(NSString *)name {
for (NSDictionary * set in myArray) {
if ([[set objectForKey:#"title"] isEqualToString:name])
\\do something
}
}
EDIT:
I've added one extra argument to the post of bshirley. Now it looks more flexible.
- (NSDictionary *)findDictionaryWithValue:(NSString*)name forKey:(NSString *)key {
__block BOOL found = NO;
__block NSDictionary *dict = nil;
[self.cardSetsArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
dict = (NSDictionary *)obj;
NSString *title = [dict valueForKey:key];
if ([title isEqualToString:name]) {
found = YES;
*stop = YES;
}
}];
if (found) {
return dict;
} else {
return nil;
}
}
Here's one possible implementation using newer API. (I also modified the method to actually return the value). Provided mostly to demonstrate that API. The assumption is that the title is unique to one dictionary within your array.
- (NSDictionary *)findDictionaryWithValueForKey:(NSString *)name {
// ivar: NSArray *myArray;
__block BOOL found = NO;
__block NSDictionary *dict = nil;
[myArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
dict = (NSDictionary *)obj;
NSString *title = [dict valueForKey:#"title"];
if ([title isEqualToString:name]) {
found = YES;
*stop = YES;
}
}];
if (found) {
return dict;
} else {
return nil;
}
}
Use filteredArrayUsingPredicate: method of the array to get all the dictionaries that satisfy your requirement.
NSPredicate * predicate = [NSPredicate predicateWithFormat:#" title MATCHES[cd] %#", name];
NSArray * matches = [myArray filteredArrayUsingPredicate:predicate];
Now matches is the array of dictionaries that have the title key equal to name.
- (void)findDictionaryWithValueForKey:(NSString)name {
for (NSDictionary * set in myArray) {
NSString *s=[NSString stringWithFormat:#"%#",[set objectForKey:#"title"]];
if ([s isEqualToString:name])
\\do something
}
OR
if (s == name])
\\do something
}
}
I will also suggest this way,it would be better if you use a break statement,
- (void)findDictionaryWithValueForKey:(NSString)name {
for (NSDictionary * set in myArray) {
if ([[set objectForKey:#"title"] isEqualToString:name])
\\do something
break;
}
}
As per the NSArray documentation,
valueForKey:
Returns an array containing the results of invoking valueForKey: using key on each of the array's objects.
- (id)valueForKey:(NSString *)key
Parameters
key
The key to retrieve.
Return Value
The value of the retrieved key.
Discussion
The returned array contains NSNull elements for each object that returns nil.
Availability
* Available in Mac OS X v10.3 and later.
EDIT:
try this,
[myArray valueForKey:#"name"];
//this will return array of values, but this actually differ from what to want
I have an NSArray of names, I want to sort them alphabetically into a UITableView and separate them into sections.
I have a tagged section at the top, being section 0. I want the names sorted aplhabetically to come after that. So all names beginning with A get put into section 1, B into section 2, and so on.
I need to be able to somehow get the number of rows for each section, and then put the objects in each section.
How do I do this?
Here is a method for a category on NSArray to do grouping:
#interface NSArray (Grouping)
- (NSArray*) groupUsingFunction: (id (*)(id, void*)) function context: (void*) context;
#end
#implementation NSArray (Grouping)
- (NSArray*) groupUsingFunction: (id (*)(id, void*)) function context: (void*) context
{
NSArray* groupedArray = nil;
NSMutableDictionary* dictionary = [NSMutableDictionary new];
if (dictionary != nil)
{
for (id item in self)
{
id key = function(item, context);
if (key != nil)
{
NSMutableArray* array = [dictionary objectForKey: key];
if (array == nil) {
array = [NSMutableArray arrayWithObject: item];
if (array != nil) {
[dictionary setObject: array forKey: key];
}
} else {
[array addObject: item];
}
}
}
groupedArray = [NSMutableArray arrayWithArray: [dictionary allValues]];
[dictionary release];
}
return groupedArray;
}
#end
You can use it like this:
id GroupNameByFirstLetter(NSString* object, void* context)
{
return [object substringToIndex: 1];
}
NSInteger SortGroupedNamesByFirstLetter(id left, id right, void* context)
{
return [[left objectAtIndex: 0] characterAtIndex: 0] - [[right objectAtIndex: 0] characterAtIndex: 0];
}
NSMutableArray* names = [NSArray arrayWithObjects: #"Stefan", #"John", #"Alex",
#"Sue", #"Aura", #"Mikki", #"Michael", #"Joe", #"Steve", #"Mac", #"Fred",
#"Faye", #"Paul", nil];
// Group the names and then sort the groups and the contents of the groups.
groupedNames_ = [[names groupUsingFunction: GroupNameByFirstLetter context: nil] retain];
[groupedNames_ sortUsingFunction: SortGroupedNamesByFirstLetter context: nil];
for (NSUInteger i = 0; i < [groupedNames_ count]; i++) {
[[groupedNames_ objectAtIndex: i] sortUsingSelector: #selector(compare:)];
}
I modified St3fans answer to be a bit more modern and work with Blocks instead:
#interface NSArray (Grouping)
- (NSArray*) groupUsingBlock:(NSString* (^)(id object)) block;
#end
- (NSArray*) groupUsingBlock:(NSString* (^)(id object)) block
{
NSArray* groupedArray = nil;
NSMutableDictionary* dictionary = [NSMutableDictionary new];
if (dictionary != nil)
{
for (id item in self)
{
id key = block(item);
if (key != nil)
{
NSMutableArray* array = [dictionary objectForKey: key];
if (array == nil) {
array = [NSMutableArray arrayWithObject: item];
if (array != nil) {
[dictionary setObject: array forKey: key];
}
} else {
[array addObject: item];
}
}
}
groupedArray = [NSMutableArray arrayWithArray: [dictionary allValues]];
[dictionary release];
}
return groupedArray;
}
You can use it like this:
NSArray *grouped = [arrayToGroup groupUsingBlock:^NSString *(id object) {
return [object valueForKey:#"name"];
}];
You should probably create an array of arrays, one for each letter, and store your names that way. While you can use a single array for storage, there's no quick way to do the segmentation you're looking for. Sorting, sure, but not section-ization.