In my project i need to compare and NSString with NSObject. How to convert NSString to NSObject. OR Is there any chance to compare NSString with NSObject.
NSString class itself inherits from NSObject class, So you can directly compare them, see below code or check this link
NSString *str = #"xyz";
NSObject *obj = #"xyz";
if([str isEqualToString:(NSString *)obj]) {
NSLog(#"comparision successful");
}
If your NSObject is indeed an NSString, you can just cast it;
NSString *text = (NSString*)someObject;
Where someObject is the object you want to be a string. If you're not sure if the object is an NSString, you can check by doing the following;
if ([someObject class] == [NSString class){
NSString *text = (NSString*)someObject;
}
Hope that helps.
Related
I mainly program in Java and can't understand why this isn't working. I'm trying to create a temporary object "Judge" in my for loop. I then want to add that object to an NSMutableArray so in the end I have an array filled with different Judge objects. After the for loop I run through all the objects in the Array and they're all the last Judge Object.
The NSLog shows that "JudgeTemp" object is being assigned the right values while in the for loop. My guess is that it's not creating a new object called JudgeTemp every time but referencing the old already created JudgeTemp.
NSMutableArray *Judges = [NSMutableArray arrayWithCapacity:30];
for (int i=0; i<[courtinfoarray count]; i++) {
Judge1= [[courtinfoarray objectAtIndex:i] componentsSeparatedByString:#"|"];
Judge *JudgeTemp=[[Judge alloc]init];
[JudgeTemp setName:[Judge1 objectAtIndex:0] picture:[Judge1 objectAtIndex:1] courtroom:[Judge1 objectAtIndex:2] phone:[Judge1 objectAtIndex:3] undergrad:[Judge1 objectAtIndex:4] lawschool:[Judge1 objectAtIndex:5] opdasa:[Judge1 objectAtIndex:6] career:[Judge1 objectAtIndex:7] judgecode:[Judge1 objectAtIndex:8]];
NSLog(#"%#",[JudgeTemp getName]);
[Judges addObject:JudgeTemp];
NSLog(#"%#",[[Judges objectAtIndex:i]getName]);
}
Judges Class
#implementation Judge
NSString *name;
NSString *picture;
NSString *courtroom;
NSString *phone;
NSString *undergrad;
NSString *lawschool;
NSString *opdasa;
NSString *career;
NSString *judgecommentcode;
-(void) setName:(NSString *)n picture:(NSString *) p courtroom:(NSString *)c phone:(NSString *)ph undergrad: (NSString *) u lawschool: (NSString *)l opdasa: (NSString *) o career: (NSString *)ca judgecode: (NSString *)jcode{
name = n;
picture = p;
courtroom = c;
phone = ph;
undergrad = u;
lawschool = l;
opdasa = o;
career = ca;
judgecommentcode = jcode;
}
-(NSString*) getName{
return name;
}
The problem is with your Judge class. When you define variables directly in your #implementation they have global scope and are not instance variables. What you need to do is put those variable declarations in your #interface instead:
#interface Judge : NSObject {
NSString *name;
NSString *picture;
NSString *courtroom;
NSString *phone;
NSString *undergrad;
NSString *lawschool;
NSString *opdasa;
NSString *career;
NSString *judgecommentcode;
}
// ...
#end
Edit: Apparently you can declare them in your #implementation, you just have to wrap them in { }. See: Instance variables declared in ObjC implementation file
-(void)displayData:(NSString *)text{
NSLog(#"DATA SEND");
NSString *string1 = [NSString stringWithFormat:text];
NSString *separate = [string1 componentsSeparatedByString:#"B"];
separate is the one that gives issue? How do I properly do this? I'm trying to perform a string split.
componentsSeparatedByString: method returns NSArray not NSString, try that:
NSArray *seperate = [string1 componentsSeparatedByString:#"B"];
what is that?
NSString *string1 = [NSString stringWithFormat:text];
Right way
NSString *string1 = [NSString stringWithFormat:#"%#",text];
or
NSString *string1 = [NSString stringWithString:text];
and then Grag answer.
In my app, I have a view where user have to fill a form. But, sometime the app crash here, in this function, that simple cacth the value field and built a url to give
-(NSString*)urlToUpload{
NSString *string1 =[[NSString alloc]init];
string1= [NSString stringWithFormat:#"?nombre="];
NSString *string2 = [string1 stringByAppendingString:nameAdded];
//crash here
NSString *string3 = [string2 stringByAppendingString:#"&horario="];
NSString *string4 = [string3 stringByAppendingString:horarioAdded];
NSString *string5 = [string4 stringByAppendingString:#"&info="];
NSString *string6 = [string5 stringByAppendingString:infoAdded];
NSString *string7 = [string6 stringByAppendingString:#"&offerta="];
NSString *string8 = [string7 stringByAppendingString:offertaAdded];
NSString *lat_string = [[[NSString alloc] initWithFormat:#"%f",locationToUpload2.latitude] autorelease];
NSString *lon_string = [[[NSString alloc] initWithFormat:#"%f",locationToUpload2.longitude] autorelease];
NSString *string9 = [string8 stringByAppendingString:#"&latitude="];
NSString *string10 = [string9 stringByAppendingString:lat_string];
NSString *string11 = [string10 stringByAppendingString:#"&longitude="];
NSString *string12 = [string11 stringByAppendingString:lon_string];
NSString *url1 = [NSString stringWithFormat:#"http://myserverside/mysql_up.php"];
NSString *url = [url1 stringByAppendingString:string12];
return url;
}
EDIT:
It seems problem appers on nameAdded when there is a white space into textField(i.e. MisterB not crash, Mister B yes ).
But I am using:
nameAdded =[[nameField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
and NSLOg give of nameAdded is Mister%20B.
The crash still appearing...
Just use a single stringWithFormat::
- (NSString *)urlToUpload {
NSString *url = [NSString stringWithFormat:#"http://myserverside/mysql_up.php?nombre=%#&horario=%#&info=%#&offerta=%#&latitude=%f&longitude=%f",
[nameAdded stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding],
[horarioAdded stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding],
[infoAdded stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding],
[offertaAdded stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding],
locationToUpload2.latitude, locationToUpload2.longitude];
return url;
}
Make sure the referenced variables are valid.
In your original code there is no need to alloc/init an NSString then assign another string to the same variable. That's a memory leak (string1).
If you really want to structure your code the way you have it, at least use an NSMutableString and append to that one mutable string. Creating over a dozen NSString variables is the wrong way to do it.
Updated: Ensure each of the strings added to the URL are properly escaped.
It looks like nameAdded may be the cause of your problems. Is it nil at that point?
Also
You are allocating a string, setting it to string1 and then immediately setting string1 to the class function stringWithFormat which allocates another string. Also you are using stringWithFormat but you aren't using any format so you could simply use NSString *string1 = #"?nombre=";
Rather than declaring all of those variables you should just use NSMutableString and build it all in one variabl
I have an nsarray with strings like this,
albumname/song42.mp3
albumname/song43.mp3 etc .
I want to remove the string "album name" and ".mp3" from the above array,and display it in a tableview as follows ,
song42
song43
then in the DidSelectRow ,i want to add the string
"http://www.domain.com/albumname/" and ".mp3" to the indepath.row element .
fo eg :
if user selects song42 in tableview ,then it must create a string like this "http://www.domain.com/albumname/song42.mp3"
How to do this ?
- [NSString stringByDeletingPathExtension] <--- This to remove
+ [NSString stringWithFormat:] <--- And this to recreate
EDIT My mistake, you first need to do this before you call the first method:
NSString *lastPath = [string lastPathComponent]; //song43.mp3
NSString *tableString = [lastPath stringByDeletingPathExtension]; //song43
You can use lastPathComponent and stringByDeletingPathExtension methods:
NSMutableArray *songs = [NSArray arrayWithCapacity:[sourceArray count]];
for (NSString *filename in sourceArray) {
[songs addObject:[[filename lastPathComponent] stringByDeletingPathExtension]];
}
use the String method componentsSeparatedByString first separate the strings using / and then . and discard what you don't need.
NSString *str="albumname/song42.mp3";
NSArray *mainStrArray = [str componentsSeparatedByString:#"/"];
NSArray remainingStrArray=[[mainStrArray objectAtIndex:1]componentsSeparatedByString:#"."];
NSString *result=[remainingStrArray objectAtIndex:0]; //here you have song42
You can use, as :
NSString *str = #"album name/song43.mp3";
str=[[str componentsSeparatedByString:#"/"][1]componentsSeparatedByString:#".mp3"][0];
NSLog(#"->%#",str); //song43
NSString *file = #"albumname/song42.mp3";
NSString *name = [[[[file componentsSeparatedByString:#"/"] objectAtIndex:1] componentsSeparatedByString:#"."] objectAtIndex:0];
I read around S.O and did Google this a fair bit but I wasn't able to find an answer to my problem...
I have an NSDictionary which is returning NSCFString's and what I need is an NSString so that I can use its doubleValue function. I can't for the life of me figure out how to turn my NSCFString's into NSStrings. I've tried the following with no success:
NSString* lng_coord = (NSString*)[dict objectForKey:key];
if ([lng_coord class] == [NSString class])
NSLog(#"lng coord is an exact match with NSString class");
else {
NSLog(#"lng coord doesn't match NSString class");
NSLog(#"The class of lng_coord is %#", [[dict objectForKey:key] class]);
}
NSLog(#"%#", lng_coord);
[CelebsAnnotation setLongitude:[lng_coord doubleValue]];
And this is the output from console:
lng coord doesn't match NSString class
The class of lng_coord is NSCFString
49.2796758
NSCFString is a private subclass of NSString, you can just use it as one.
Because of such patterns like class clusters, you shouldn't directly compare the classes here - use -isKindOfClass: instead:
if ([lng_coord isKindOfClass:[NSString class]]) {
// ...