I'm developing for iOS 5, say I have 2 arrays, the second only contains items contained on the first one.
I want to remove this object in every array it's present.
So, is there a way to easily remove an object from all arrays that contains it?
NSMutableArray *totalArray = [ [ NSMutableArray alloc] init];
//here i assume u want to delete NSString object vijay in all arrays
NSString *toDelete=#"vijay";
[totalArray addObject:firstArray];
[totalArray addObject:secondArray];
for (NSMutableArray *arr in totalArray) {
if ([arr containsObject:toDelete]) {
[arr removeObject:toDelete];
}
}
NSLog(#"firstarry : %# \n\n",firstArray);
NSLog(#"secondarray : %# \n\n",secondArray);
Related
I have to 2 NSMutableArrays containing NSMutableDictionarys. I need to verify the dictionaries in one of the arrays exists in the other array. How can I do this?
I'm not sure if this is the best approach but it is an easy one. I created a method to verify if a NSDictionary is present inside a NSArray. Inside this function, I convert the NSDictionarys to NSStrings and compare them.
- (BOOL)verifyIfDictionary:(NSDictionary *)dict existsInsideArray:(NSArray *)array
{
BOOL result = NO;
NSString *dictStr = [NSString stringWithFormat:#"%#",dict]; // convert dictionary to string
for (NSDictionary *d in arrayOfDictionaries)
{
NSString *dStr = [NSString stringWithFormat:#"%#",dict]; // same conversion as above conversion
// now, I just have to compare the resulting strings
if ([dictStr isEqualToString:dStr])
result = YES;
}
return result;
}
Now you just have to iterate through one of your NSArrays and use this method, like this:
NSArray *arrayOfDictionaries1;
NSArray *arrayOfDictionaries2;
// initialize them, fill with data, do your processing.. etc, etc...
// then, when you want to verify:
for (NSDictionary *dict in arrayOfDictionaries1)
{
if ([self verifyIfDictionary:dict existsInsideArray:arrayOfDictionaries2])
{
NSLog(#"exists!");
}
}
To check if array1 contains all of the items in array2:
NSMutableArray *mutableArrayToCheck = [array2 mutableCopy];
[mutableArrayToCheck removeObjectsInArray:array1];
if (array2.count > 0 && mutableArrayToCheck.count == 0) {
// array2 contains all the items in array1
}
Ignore the type of the contents of the arrays for a second, just think of numbers. We have 2 arrays:
array1 = [ 1, 2, 3 ]
array2 = [ 1, 3 ]
If we remove the items in array1 from array2, and the result is an empty array, then we know that all of the items in array2 were also in array1.
removeObjectsInArray: does this for us by searching through the array and comparing each item. We just need to check the result.
This works no matter what the contents of the array are, so long as they implement hash and isEqual:.
There is an array in my app having multiple same values in it. I need to delete only one value at a time from array whether it has same more values in it.
Level1 Business,
Level2 Economy,
Level2 Economy,
Level1 Business
How this can be achieved, and main thing is that these values are dynamic these can be more or less also. Please guide for above.
Below is what i tried.
if([arr containsObject:[NSString stringWithFormat:#"%d",ind]]){
[arr removeObject:[NSString stringWithFormat:#"%d",ind]];
}
This thing removes all similar entries, not required. Thanks in advance.
try like this,
NSArray *array = [NSArray arrayWithObjects:#"Level1 Business", #"Level2 Economy", #"Level2 Economy", #"Level1 Business", nil];
NSMutableArray *mainarray=[[NSMutableArray alloc]initWithArray:array];
int n=[mainarray indexOfObject:#"Level2 Economy"];//it gives first occurence of the object in that array
if(n<[mainarray count]) // if the object not exist then it gives garbage value that's why here we have to take some condition
[mainarray removeObjectAtIndex:n];
NSLog(#"%#",mainarray);
O/P:-
(
"Level1 Business",
"Level2 Economy",
"Level1 Business"
)
As you say,
[array removeObject:#"SomeObject"];
removes all instances of where isEqual: returns YES. To remove only the first instance, you can use something like
NSUInteger index = [array indexOfObject:#"SomeObject"];
if(index != NSNotFound) {
[array removeObjectAtIndex:index];
}
Use [arr removeObjectAtIndex:yourIndex ] to remove your object at perticular postion at dynamic
Sample Code :
NSMutableArray *arr = [[NSMutableArray alloc]initWithObjects:#"hello",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",#"hi",nil];
NSUInteger obj = [arr indexOfObject:#"hi"]; //Returns the lowest integer of the specified object
[arr removeObjectAtIndex:obj]; //removes the object from the array
NSLog(#"%#",arr);
In your Case :
if([arr containsObject:[NSString stringWithFormat:#"%d",ind]])
{
NSUInteger obj = [arr indexOfObject:[NSString stringWithFormat:#"%d",ind]]; //Returns the lowest integer of the specified object
[arr removeObjectAtIndex:obj];
}
Here your requirement is like definition of NSSet, which contains unique objects only.
But this will implies only if both the same value objects, are really in referring to same memory location as well.
If this is the case then and then, you can try code mentioned below:
// create set from an array
NSSet *telephoneSet = [NSSet setWithArray: myArray];
// create array from a set
NSMutableArray *array = [NSMutableArray arrayWithArray:[set allObjects]];
I don't know whether it will work for your requirement or not. But for that, it would be required to check the object equality level.
Still it might help you as an less line of code.
NSMutableArray *uniques= [[NSMutableArray alloc] init];
for (NSString *word in duplicateWordsArray){
if (!uniques.contains(word)){
[ uniques addObject:word];
}
}
I wrote this from my phone so it isn't formatted for code, but this will do it for you quickly and you'll have an array (uniquearray) that has unique words. Then you can use that one or set your original array = to unique array
NSArray *input = [NSArray arrayWithObjects:#"Level1 Business", #"Level2 Economy", #"Level2 Economy", #"Level1 Business", nil];
NSMutableArray *output = [[NSMutableArray alloc] init];
[output addObject:[input objectAtIndex:0]];
for(NSString *value in input) {
if(![output containsObject:value])
[output addObject:value];
}
I am new to iphone.I have an array which contains the objects like below
"04_Num",
"04_Num/04Num.m3u",
"04_Num/04Num001.mp3",
"04_Num/04Num002.mp3",
"04_Num/04Num003.mp3",
"04_Num/04Num004.mp3",
"04_Num/04Num005.mp3",
"04_Num/04Num006.mp3",
"04_Num/04Num007.mp3",
"04_Num/04Num008.mp3",
"04_Num/04Num009.mp3",
"04_Num/04Num010.mp3",
"04_Num/04Num011.mp3",
"04_Num/04Num012.mp3",
"04_Num/04Num013.mp3",
"04_Num/04Num014.mp3",
"04_Num/04Num015.mp3",
"04_Num/04Num016.mp3",
"04_Num/04Num017.mp3",
"04_Num/04Num018.mp3",
"04_Num/04Num019.mp3",
"04_Num/04Num020.mp3",
"04_Num/04Num021.mp3",
"04_Num/04Num022.mp3",
"04_Num/04Num023.mp3",
"04_Num/04Num024.mp3",
"04_Num/04Num025.mp3",
"04_Num/04Num026.mp3",
"04_Num/04Num027.mp3",
"04_Num/04Num028.mp3",
"04_Num/04Num029.mp3",
"04_Num/04Num030.mp3",
"04_Num/04Num031.mp3",
"04_Num/04Num032.mp3",
"04_Num/04Num033.mp3",
"04_Num/04Num034.mp3",
"04_Num/04Num035.mp3",
"04_Num/04Num036.mp3"
but here i want the objects only which contains .mp3 extension and then i have to place those objects into another array
how it is possible if any body know this please help me...
You can iterate and get only the one that has .mp3
Like so
//yourArrayThatContainsAllStrings contains all the strings
NSMutableArray *arrayOfMp3 = [[NSMutableArray alloc] init];
for (NSString *str in yourArrayThatContainsAllStrings) {
if ([str rangeOfString:#".mp3"].location != NSNotFound) {
[arrayOfMp3 addObject:str];
}
}
//arrayOfMp3 will contain only the .mp3 files
NSMutableArray *mpthrees = [[NSMutableArray alloc] initWithCapacity:0];
for (NSString *file in songs) //Where songs is the array with the paths you have provided
{
BOOL isMpthree = [[file pathExtension] isEqualToString:#"mp3"];
if (isMpthree) [mpthrees addObject:file];
}
// Now mpthrees array holds only paths pointing to .mp3 files
// Let's call your array of strings as stringsArray
NSMutableArray *filteredArray = [[NSMutableArray alloc] init];
for (NSString *str in stringsArray) {
if ([str hasSuffix:#".mp3"]) {
[filteredArray addObject:str];
} }
//filteredArray will contain only the strings ending with ".mp3"
P.S. Since you're just beginning Objective C, i would like to reiterate that Objective C NSString objects always start with an # symbol. #"04_Num/04Num001.mp3"
I am getting below response into the nsarray when I used the JSON parsing from my required URL but here I don't like to get 2,1,4,4,6,5,8,7,10,9,12 and 11 in single array I have to get total response into two arrays I mean one array set will consists 2,4,6,8,10 and other array set must be 3,5,7,9 and 11.
So how is the code for separation of single array response into two arrays in iPhone?
"(\n 2,\n 1\n)",
"(\n 4,\n 3\n)",
"(\n 6,\n 5\n)",
"(\n 8,\n 7\n)",
"(\n 10,\n 9\n)",
"(\n 12,\n 11\n)"
If you combine every number into one large array, you could feasibly test if each number is even or odd with a simple if-else in a for-in loop. Maybe like this:
-(NSArray*)parseJSONIntoArrays:(NSArray*)array {
NSMutableArray *evenNumbers = [[NSMutableArray alloc]init];
NSMutableArray *oddNumbers = [[NSMutableArray alloc]init];
for (NSNumber *number in array) {
if (([number intValue] %2) == 0) {
//even
[evenNumbers addObject:number];
}
else {
//odd
[oddNumbers addObject:number];
}
}
return [[NSArray alloc]initWithObjects:evenNumbers, oddNumbers, nil];
}
To split an array, you usually need to loop through all of the values and use an IF ELSE structure to decide which array to put the values in. Also, you need to use NSMutableArray instead of NSArray. Something like this:
NSMutableArray *evenNumbers = [NSMutableArray new];
NSMutableArray *oddNumbers = [NSMutableArray new];
for (NSNumber *value in myArray) {
if ([value intValue] % 2 == 0) {
[evenNumbers addObject:value];
} else {
[oddNumbers addObject:value];
}
}
I want to know that how can I add NSMutableArray in to an NSMutableArray so that previous data should not lost, and new data will be added on next indexes.
If you don't understand it then you can ask again to me,
I will appraise the right answer.
my code is as below
-(void)setArray1:(NSMutableArray *)arrayValueFromNew
{
self.myArray=arrayValueFromNew;
myArray2 = [[NSMutableArray alloc] initWithArray:arrayValueFromNew];
for(int i=0;i<[myArray2 count];i++)
{
[myArray addObject:[myArray2 objectAtIndex:i]];
}
}
In your code, myArray and myArray2, both have same objects as you are assigning the arrayValueFromNew array to both. So it kind of doesn't make sense.
But to answer your question 'how to add one array to another?' do :
[mutableArray1
addObjectsFromArray:array2];
EDIT:
this is how your method should look
-(void)setArray1:(NSMutableArray *)arrayValueFromNew
{
if(!self.myArray)
{
self.myArray = arrayValueFromNew;
}
else
{
[self.myArray addObjectsFromArray:arrayValueFromNew];
}
}
Your 'myArray must be initialized. You can initialize it in viewDidLoad or init:
self.myArray = [[NSMutableArray alloc]
initWithCapacity:1];
NSMutableArray *array1 = [NSMutableArray array], *array2 = [NSMutableArray array];
// add some objects to the arrays
[array1 addObjectsFromArray:array2];
//array1 now contains all the objects originally in array1 and array2
This will work,
NSMutableArray *mutarr=[[NSMutableArray alloc]initWithArray: array1]
It looks like you just want a new copy of the old array. There is a handy function for that
NSMutableArray *newArray = [oldArray mutableCopy];
Remember that you've used copy in getting this array so you are responsible for managing the memory of newArray
EDIT
What is your code doing?
-(void)setArray1:(NSMutableArray *)arrayValueFromNew //1
{
self.myArray=arrayValueFromNew; //2
myArray2 = [[NSMutableArray alloc] initWithArray:arrayValueFromNew]; //3
for(int i=0;i<[myArray2 count];i++)
{
[myArray addObject:[myArray2 objectAtIndex:i]]; //4
}
}
This looks like a setter for a property array1
You are setting the property 'array' to arrayValueFromNew. Since I don't know whether this property has been declared with retain or copy I don't know whether array is a pointer to arrayValueFromNew or a pointer to a copy of arrayValueFromNew
You set myArray2 to be a new array that contains the objects of arrayValueFromNew
For each object in myArray2 (which are the objects from arrayValueFromNew. see point 3) you add this object to myArray. Assuming myArray is an NSMutableArray it started with the objects from arrayValueFromNew which you have now added again. It contains each item in arrayValueFromNew twice.