NSString *title = [myWebView
stringByEvaluatingJavaScriptFromString:#"document.title"];
NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:8];
int j = 0;
int i=0;
int count=0;
int len;
len = [title length];
for(i=0;i<len;i++){
NSString *c = [title substringWithRange:NSMakeRange(i, 1)];
if([c isEqualToString:#","])
{
//array[count]= [title substringWithRange:NSMakeRange(j, 2)];
NSString *xxx = [title substringWithRange:NSMakeRange(j,(i-j))];
NSLog(xxx);
//insert the string into array
[array insertObject:xxx atIndex:count];
j=i;
count = count + 1;
}
}
My app always crashes at the line
[c isEqualToString:#","]
and gives the error - Thread1 : Program received signal: "SIGBART".
I know for sure that the problem is occurring while comparing strings since the app runs if I remove that one line of code.
Can someone please help? Thanks
Consider using:
- (NSArray *)componentsSeparatedByString:(NSString *)separator
Example:
NSString *title = [myWebView stringByEvaluatingJavaScriptFromString:#"document.title"];
NSMutableArray *array = [title componentsSeparatedByString:#","];
If I ends up longer than the string, or is undefined, you've got issues. If you replace i with 1, it doesn't crash, right?
Incidentally, you could use:
unichar c = [title characterAtIndex:i];
Related
I'm having an issue with the following code. I want the resultant multiLineTitle to look like this
Each
Word
Should
Have
Its
Own
Line
But when I run this program, multiLineTitle ends up null. Can anyone spot the issue?
NSString *title = "Each Word Should Have Its Own Line";
NSString *multiLineTitle;
NSArray *words = [title componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
words = [words filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:#"SELF != ''"]];
for (int len = 0; len < [words count]; len++){
multiLineTitle = [multiLineTitle stringByAppendingFormat:#"%# \n", words[len]];
}
assign empty string to multiLineTitle or allocate memory for multiLineTitle.
NSString *multiLineTitle = #"";
or
NSString *multiLineTitle = [[NSString alloc]init];
solution....
NSString *title =#"Each Word Should Have Its Own Line";
NSMutableString *multiLineTitle =[[NSMutableString alloc] init];
NSArray *words = [title componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
words = [words filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:#"SELF != ''"]];
for (int len = 0; len < [words count]; len++){
[multiLineTitle appendFormat:#"%#\n",[words objectAtIndex:len]];
}
NSLog(#"multiLineTitle:%#",multiLineTitle);
ans:
multiLineTitle:Each
Word
Should
Have
Its
Own
Line
Hello and thanks for the help
Why is this for loop not getting called. (contents is an nsmutableArray)
NSString *setBiz = [[NSString alloc]init];
setBiz = #"MomAndPop";
NSLog(#"??????????listby???????????%#\n",setBiz);
for (NSDictionary *key in self.contents) {
NSLog(#"hi inside loopppp"); //I never see this ????????
NSString *c = [key objectForKey:#"BizName"];
NSString *string = [NSString stringWithFormat:#"%#", key]; //random test
if ([c isEqualToString:setBiz]) {
NSLog(#"gotch you");
}
}
The most likely answer is that self.contents has no elements inside of it.
Place this before your loop to output the number of elements in the loop:
NSLog(#"self.contents.count: %lu", self.contents.count);
I'm trying to re-arrange words into alphabetical order. For example, tomato would become amoott, or stack would become ackst.
I've found some methods to do this in C with char arrays, but I'm having issues getting that to work within the confines of the NSString object.
Is there an easier way to do it within the NSString object itself?
You could store each of the string's characters into an NSArray of NSNumber objects and then sort that. Seems a bit expensive, so I would perhaps just use qsort() instead.
Here it's provided as an Objective-C category (untested):
NSString+SortExtension.h:
#import <Foundation/Foundation.h>
#interface NSString (SortExtension)
- (NSString *)sorted;
#end
NSString+SortExtension.m:
#import "NSString+SortExtension.h"
#implementation NSString (SortExtension)
- (NSString *)sorted
{
// init
NSUInteger length = [self length];
unichar *chars = (unichar *)malloc(sizeof(unichar) * length);
// extract
[self getCharacters:chars range:NSMakeRange(0, length)];
// sort (for western alphabets only)
qsort_b(chars, length, sizeof(unichar), ^(const void *l, const void *r) {
unichar left = *(unichar *)l;
unichar right = *(unichar *)r;
return (int)(left - right);
});
// recreate
NSString *sorted = [NSString stringWithCharacters:chars length:length];
// clean-up
free(chars);
return sorted;
}
#end
I think separate the string to an array of string(each string in the array contains only one char from the original string). Then sort the array will be OK. This is not efficient but is enough when the string is not very long. I've tested the code.
NSString *str = #"stack";
NSMutableArray *charArray = [NSMutableArray arrayWithCapacity:str.length];
for (int i=0; i<str.length; ++i) {
NSString *charStr = [str substringWithRange:NSMakeRange(i, 1)];
[charArray addObject:charStr];
}
NSString *sortedStr = [[charArray sortedArrayUsingSelector:#selector(localizedCaseInsensitiveCompare:)] componentsJoinedByString:#""];
// --------- Function To Make an Array from String
NSArray *makeArrayFromString(NSString *my_string) {
NSMutableArray *array = [[NSMutableArray alloc] init];
for (int i = 0; i < my_string.length; i ++) {
[array addObject:[NSString stringWithFormat:#"%c", [my_string characterAtIndex:i]]];
}
return array;
}
// --------- Function To Sort Array
NSArray *sortArrayAlphabetically(NSArray *my_array) {
my_array= [my_array sortedArrayUsingSelector:#selector(localizedCaseInsensitiveCompare:)];
return my_array;
}
// --------- Function Combine Array To Single String
NSString *combineArrayIntoString(NSArray *my_array) {
NSString * combinedString = [[my_array valueForKey:#"description"] componentsJoinedByString:#""];
return combinedString;
}
// Now you can call the functions as in below where string_to_arrange is your string
NSArray *blowUpArray;
blowUpArray = makeArrayFromString(string_to_arrange);
blowUpArray = sortArrayAlphabetically(blowUpArray);
NSString *arrayToString= combineArrayIntoString(blowUpArray);
NSLog(#"arranged string = %#",arrayToString);
Just another example using NSMutableString and sortUsingComparator:
NSMutableString *mutableString = [[NSMutableString alloc] initWithString:#"tomat"];
[mutableString appendString:#"o"];
NSLog(#"Orignal string: %#", mutableString);
NSMutableArray *charArray = [NSMutableArray array];
for (int i = 0; i < mutableString.length; ++i) {
[charArray addObject:[NSNumber numberWithChar:[mutableString characterAtIndex:i]]];
}
[charArray sortUsingComparator:^NSComparisonResult(id _Nonnull obj1, id _Nonnull obj2) {
if ([obj1 charValue] < [obj2 charValue]) return NSOrderedAscending;
return NSOrderedDescending;
}];
[mutableString setString:#""];
for (int i = 0; i < charArray.count; ++i) {
[mutableString appendFormat:#"%c", [charArray[i] charValue]];
}
NSLog(#"Sorted string: %#", mutableString);
Output:
Orignal string: tomato
Sorted string: amoott
I have a NSMutableArray where i want to replace the sign | into a ; how can i do that?
NSMutableArray *paths = [dic valueForKey:#"PATH"];
NSLog(#"pathArr ", paths)
pathArr (
(
"29858,39812;29858,39812;29925,39804;29936,39803;29949,39802;29961,39801;30146,39782;30173,39779;30220,39774;30222,39774|30215,39775;30173,39779;30146,39782;29961,39801;29949,39802;29936,39803;29925,39804;29858,39812;29858,39812;29856,39812;29800,39819;29668,39843;29650,39847;29613,39855;29613,39855;29613,39856;29605,39857;29603,39867;29603,39867;29599,39892;29596,39909;29587,39957;29571,40018;29563,40038;29560,40043"
)
)
Update
This is where i got my path from
NSArray *BusRoute = alightDesc;
int i;
int count = [BusRoute count];
for (i = 0; i < count; i++)
{
NSLog (#"BusRoute = %#", [BusRoute objectAtIndex: i]);
NSDictionary *dic = [BusRoute objectAtIndex: i];
NSMutableArray *paths = [dic valueForKey:#"PATH"];
}
Provide that your object in the array path is string, you can do this
NSMutableArray *path2=[[NSMutableArray alloc]initWithArray:nil];
for (NSObject *obect in path) {
for (NSString *string in (NSArray*)obect) {
[path2 addObject:[string stringByReplacingOccurrencesOfString:#"|" withString:#","]];
}
}
NSLog(#"pathArr %# ", path2);
your array paths contains an another array which has string as object.
Hope this helps
//Copy the Array into a String
NSString *str = [paths componentsJoinedByString: #""];
//then replace the "|"
str = [str stringByReplacingOccurrencesOfString:#"|" withString:#";"];
i did this to replace a string in a .plist so it might work for you
array1 = [NSMutableArray arrayWithContentsOfFile:Path1];
NSString *item = [#"dfdfDF"];
[array1 replaceObjectAtIndex:1 withObject:item];
[array1 writeToFile:Path1 atomically:YES];
NSLog(#"count: %#", [array1 objectAtIndex:1]);
you may cast or convert paths to NSString and then do:
paths = (NSString *) [paths stringByReplacingOccurrencesOfString:#"|" withString:#";"];
if this does't work, create new NSString instance that containing pathArr text, invoke replaceOccurrences method and do invert conversion
NSMutableString *tempStr = [[NSMutableString alloc] init];
for (int i = 0; i < [paths count]; i++)
{
[tempStr appendString:[path objectAtIndex:i]];
}
then use this method for tempStr. And then try:
NSArray *newPaths = [tempStr componentsSeparatedByString:#";"];
may be last method not completely correct, so try experiment with it.
Uh, why don't you just go:
NSString *cleanedString = [[[dic valueForKey:#"PATH"] objectAtIndex:0] stringByReplacingOccurrencesOfString:#";" withString:#"|"];
If there are more than one nested array, you can go
for(int i = 0; i < [[dic valueForKey:#"PATH"] count]; i++)
{
NSString *cleanedString = [[[dic valueForKey:#"PATH"] objectAtIndex:i] stringByReplacingOccurrencesOfString:#";" withString:#"|"];
// do something with cleanedString
}
here is yet another silly question from me!
NSString *hex1 = #"50be4f3de4";
NSString *hex2 = #"30bf69a299";
/* some stuff like result = hex1^hex2; */
NSString *result = #"6001269f7d";
I have a hex value as a string, stored in two diff. variables. i need to Xor them and the result should be in another string variables?
i tried them by converting string --> NSData --> bytes array --> xor'ing them ...but i have no success.....
thank you in advance...
You have to convert every character to Base16(for hexadecimal) format first.Then you should proceed with XORing those characters.You can use the strtol() function to achieve this purpose.
NSString *hex1 = #"50be4f3de4";
NSString *hex2 = #"30bf69a299";
NSMutableArray *hexArray1 = [self splitStringIntoChars:hex1];
NSMutableArray *hexArray2 = [self splitStringIntoChars:hex2];
NSMutableString *str = [NSMutableString new];
for (int i=0; i<[hexArray1 count]; i++ )
{
/*Convert to base 16*/
int a=(unsigned char)strtol([[hexArray1 objectAtIndex:i] UTF8String], NULL, 16);
int b=(unsigned char)strtol([[hexArray2 objectAtIndex:i] UTF8String], NULL, 16);
char encrypted = a ^ b;
NSLog(#"%x",encrypted);
[str appendFormat:#"%x",encrypted];
}
NSLog(#"%#",str);
Utility method that i used to split characters of the string
-(NSMutableArray*)splitStringIntoChars:(NSString*)argStr{
NSMutableArray *characters = [[NSMutableArray alloc]
initWithCapacity:[argStr length]];
for (int i=0; i < [argStr length]; i++)
{
NSString *ichar = [NSString stringWithFormat:#"%c", [argStr characterAtIndex:i ]];
[characters addObject:ichar];
}
return characters;
}
Hope it helps!!