I have 3 strings.
NSString *hour1 = #"10:00";
NSString *hour2 = #"6:00";
NSString *hour3 = #"9:00";
How can I check which string has a bigger value? -> 10:00 > 9:00 > 6:00
Thanks in advance!
Add the strings into an array,
NSString *hour1 = #"10:00";
NSString *hour2 = #"6:00";
NSString *hour3 = #"9:00";
NSArray *hours = [NSArray arrayWithObjects:hour1, hour2, hour3, nil];
Then sort the array,
NSArray *result = [hours sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2){
return ([obj1 compare:obj2 options:NSNumericSearch] == NSOrderedAscending);
}];
NSString *hour1 = #"10:00";
NSString *hour2 = #"6:00";
NSString *hour3 = #"9:00";
// Convert the hours over to int's such as 1000, 600, and 900.
int hour1AsInt = [[hour1 stringByReplacingOccurrencesOfString:#":" withString:#""] intValue];
int hour2AsInt = [[hour2 stringByReplacingOccurrencesOfString:#":" withString:#""] intValue];
int hour3AsInt = [[hour3 stringByReplacingOccurrencesOfString:#":" withString:#""] intValue];
// Make the comparison's... This could be more efficient but works well and is easy to follow:
if (hour1AsInt > hour2AsInt) {
if (hour1AsInt > hour3AsInt) {
NSLog(#"Hour 1 is biggest");
return;
}
}
if (hour2AsInt > hour1AsInt) {
if (hour2AsInt > hour3AsInt) {
NSLog(#"Hour 2 is biggest");
return;
}
}
if (hour3AsInt > hour1AsInt) {
if (hour3AsInt > hour2AsInt) {
NSLog(#"Hour 3 is biggest");
return;
}
}
You should be able to use localizedStandardCompare:
NSLog(#"%ld",[hour1 localizedStandardCompare:hour2]);
Related
What is the easiest way to format a string "1234567890123456789" to "1234 5678 9012 3456 789" in IOS?
Try this:
-(NSString *) correctString:(NSString *) anyStr {
NSMutableString *str=[NSMutableString stringWithString:anyStr];
int indx=4;
while (indx<str.length) {
[str insertString:#" " atIndex:indx];
indx +=5;
}
anyStr=str;
return anyStr;
}
For that particular format, you could do something like the following, which extracts the individual substrings:
NSString *string = #"1234567890123456789";
NSMutableArray *array = [NSMutableArray array];
for (NSInteger i = 0; i < [string length]; i += 4)
[array addObject:[string substringWithRange:NSMakeRange(i, MIN(4, [string length] - i))]];
NSString *result = [array componentsJoinedByString:#" "];
The thing is, not all credit cards conform to the xxxx xxxx xxxx xxxx format. E.g., Amex uses a xxxx xxxxxx xxxxx format. You really should look at the first digits of the card, determine the type of card, and format it accordingly.
You asked if you could do it with a regular expression. Consider this regex:
NSString *result = [string stringByReplacingOccurrencesOfString:#"^[\\s-]*([0-9]{4})[\\s-]*([0-9]{4})[\\s-]*([0-9]{4})[\\s-]*([0-9]{4})[\\s-]*([0-9]{3})[\\s-]*$"
withString:#"$1 $2 $3 $4 $5"
options:NSRegularExpressionSearch
range:NSMakeRange(0, [string length])];
That will convert any of the following:
#"1234567890123456789"
#"1234-5678-9012-3456-789"
#" 1234567890123456789 "
into:
#"1234 5678 9012 3456 789"
While you could use regular expression, it's sufficiently opaque that I wouldn't particularly advise it. But it can be done.
I wrote code.
NSMutableString *string = #"1234567890123456789";
NSInteger *ip = 4;
for (NSInteger i = 0; i*4 < [string length] ; i++)
{
[string insertString:#" " atIndex:ip];
ip = ip+5;
}
I propose to use NSString category. In not ARC just add autorelease after self copy.
My variant will not add spaces after last digits quarter if it is not nescessary.
Applicable to use in UITextField.
- (NSString *)creditCardNumberFormatedString {
NSString *string = [self copy];
NSUInteger length = string.length;
if (length >= 17) {
string = [string substringToIndex:16];
length = 16;
}
BOOL isSpaceRequired = YES;
if (length == 4) {
isSpaceRequired = NO;
}
NSString *newString = [NSString new];
while (string.length > 0) {
NSString *subString = [string substringToIndex:MIN(string.length, 4)];
newString = [newString stringByAppendingString:subString];
if (subString.length == 4 && isSpaceRequired) {
newString = [newString stringByAppendingString:#" "];
}
string = [string substringFromIndex:MIN(string.length, 4)];
if (string.length <= 4) {
isSpaceRequired = NO;
}
}
return newString;
}
Here is a Swift extension:
extension String {
var pairs: [String] {
var result: [String] = []
let chars = Array(characters)
for index in 0.stride(to: chars.count, by: 4) {
result.append(String(chars[index..<min(index+4, chars.count)]))
}
return result
}
}
To use:
let string : String = "1234567890123456789"
let finalString = string.pairs.joinWithSeparator(" ") //1234 5678 9012 3456 789
print(finalString)
For Swift 3:
extension String {
var pairs: [String] {
var result: [String] = []
let chars = Array(characters)
for index in stride(from: 0, to: chars.count, by: 4){
result.append(String(chars[index..<min(index+4, chars.count)]))
}
return result
}
}
For text bozo__foo!!bar.baz, how to split an NSString containing this into (bozo, foo, bar, baz)?
That is, separe it in components with strings (delimiters) __, !! and ..
You can split the strings using NSCharacterSet. Try this
NSString *test=#"bozo__foo!!bar.baz";
NSString *sep = #"_!.";
NSCharacterSet *set = [NSCharacterSet characterSetWithCharactersInString:sep];
NSArray *temp=[test componentsSeparatedByCharactersInSet:set];
NSLog(#"temp=%#",temp);
I'm aware that this question has already been answered but this is a way to separate strings using multiple strings. This is a category to NSString.
- (NSArray<NSString *> *)componentsSeparatedByStrings:(NSArray<NSString *> *)separators
{
NSMutableArray<NSString *> *components = [[NSMutableArray alloc] init];
unichar buffer[self.length + 1];
NSInteger currentOrigin = 0;
NSInteger currentLength = 0;
[self getCharacters:buffer];
for(NSInteger i = 0; i < self.length; i++)
{
unichar currentChar = buffer[i];
currentLength++;
for(NSInteger n = 0; n < separators.count; n++)
{
NSString *currentDivider = [separators objectAtIndex:n];
if(currentDivider.length == 0)
{
return #[self];
}
else if(currentDivider.length > 1)
{
BOOL goodMatch = NO;
for(NSInteger x = 0; x < currentDivider.length; x++)
{
unichar charInDivider = [currentDivider characterAtIndex:x];
if(charInDivider == currentChar)
{
goodMatch = YES;
}
else
{
goodMatch = NO;
break;
}
if(goodMatch == YES && ((x + 1) != currentDivider.length))
{
i++;
currentLength++;
currentChar = buffer[i];
}
}
if(goodMatch == YES)
{
NSRange newComponentRange = NSMakeRange(currentOrigin, (currentLength - currentDivider.length));
NSString *newComponent = [self substringWithRange:newComponentRange];
currentOrigin = (i + 1);
currentLength = 0;
[components addObject:newComponent];
NSLog(#"%#", components);
}
}
else // If current divider is only one character long.
{
if([currentDivider characterAtIndex:0] == currentChar)
{
NSRange newComponentRange = NSMakeRange(currentOrigin, (currentLength - 1));
NSString *newComponent = [self substringWithRange:newComponentRange];
currentOrigin = (i + 1);
currentLength = 0;
[components addObject:newComponent];
break;
}
}
}
// Handle the end of the string.
if((i + 1) == self.length)
{
NSRange newComponentRange = NSMakeRange(currentOrigin, currentLength);
NSString *newComponent = [self substringWithRange:newComponentRange];
currentOrigin = 0;
currentLength = 0;
[components addObject:newComponent];
}
}
return components;
}
Example: "ABCD__EFGHI__JKLMNOP-QRST.UV_WXYZ"
NSLog(#"%#", [test componentsSeparatedByStrings:#[#"__", #"-", #"."]]);
Log Result: "(ABCD, EFGHI, JKLMNOP, QRST, "UV_WXYZ")"
NSString *text = #"bozo__foo!!bar.baz";
NSArray *split1 = [text componentsSeparatedByString:#"__"];
NSArray *split2 = [[split1 lastObject] componentsSeparatedByString:#"!!"];
NSArray *split3 = [[split2 lastObject] componentsSeparatedByString:#"."];
NSLog(#"%#, %#, %#, %#", split1[0], split2[0], split3[0], split3[1]);
More functional solution is to apply -componentsSeparatedByString: recursively, for each component, which was derived during previous separator application:
NSString Category
- (NSMutableArray<NSString *> *)gvr_componentsSeparatedByStrings:(NSArray<NSString *> *)separators {
if (separators.count == 0) {
return [NSMutableArray arrayWithObject:self];
}
NSString *separator = [separators firstObject];
NSArray *reducedSeparators = [separators gvr_arrayByRemovingFirstObject];
NSArray *components = [self componentsSeparatedByString:separator];
NSMutableArray *result = [NSMutableArray new];
for (NSString *component in components) {
NSMutableArray *subResult = [component gvr_componentsSeparatedByStrings:reducedSeparators];
[result addObjectsFromArray:subResult];
}
return result;
}
NSArray Category
- (NSArray *)gvr_arrayByRemovingFirstObject {
NSMutableArray *result = [NSMutableArray new];
for (NSInteger i = 1; i < self.count; i++) {
[result addObject:self[i]];
}
return [result copy];
}
I solved it for my project by looking for the longest separator, replacing the others with this one, then do the separation on the only one left.
Try this:
NSString *test = #"bozo__foo!!bar.baz";
test = [test stringByReplacingOccurrencesOfString:#"!!" withString:#"__"];
test = [test stringByReplacingOccurrencesOfString:#"." withString:#"__"];
NSArray<NSString *> *parts = [test componentsSeparatedByString:#"__"];
I need to substring to the 2nd comma in an NSString.
Input:
NSString *input = #"title, price, Camry, $19798, active";
Desired Output:
NSString *output = #"title, price";
Thanks!
UPDATE:
I have the following but the problem is it needs to skip the last comma:
NSString *output = [input rangeOfString:#"," options:NSBackwardsSearch];
Try this:
- (NSString *)substringOfString:(NSString *)base untilNthOccurrence:(NSInteger)n ofString:(NSString *)delim
{
NSScanner *scanner = [NSScanner scannerWithString:base];
NSInteger i;
for (i = 0; i < n; i++)
{
[scanner scanUpToString:delim intoString:NULL];
[scanner scanString:delim intoString:NULL];
}
return [base substringToIndex:scanner.scanLocation - delim.length];
}
this code should do what you need:
NSString *input = #"title, price, Camry, $19798, active";
NSArray *array = [input componentsSeparatedByString:#","];
NSArray *subArray = [array subarrayWithRange:NSMakeRange(0, 2)];
NSString *output = [subArray componentsJoinedByString:#","];
NSLog(output);
You could split -> splice -> join that string like this in objc:
NSString *input = #"title, price, Camry, $19798, active";
// split by ", "
NSArray *elements = [input componentsSeparatedByString: #", "];
// grab the subarray
NSArray *subelements = [elements subarrayWithRange: NSMakeRange(0, 2)];
// concat by ", " again
NSString *output = [subelements componentsJoinedByString:#", "];
You can try something like this:
NSArray *items = [list componentsSeparatedByString:#", "];
NSString result = #"";
result = [result stringByAppendingString:[items objectAtIndex:0]];
result = [result stringByAppendingString:#", "];
result = [result stringByAppendingString:[items objectAtIndex:1]];
You have to check you have at least two items if you want avoid an exception.
There's really nothing wrong with simply writing the code to do what you want. Eg:
int commaCount = 0;
int i;
for (i = 0; i < input.count; i++) {
if ([input characterAtIndex:i] == (unichar) ',') {
commaCount++;
if (commaCount == 2) break;
}
}
NSString output = nil;
if (commaCount == 2) {
output = [input substringToIndex:i];
}
You could create an NSString category to handle finding nth occurrences of any string. This is example is for ARC.
//NSString+MyExtension.h
#interface NSString(MyExtension)
-(NSString*)substringToNthOccurrence:(NSUInteger)nth
ofString:(NSString*)string;
-(NSString*)substringToNthOccurrence:(NSUInteger)nth
ofString:(NSString*)string
options:(NSStringCompareOptions)options;
#end
#implementation NSString(MyExtension)
-(NSString*)substringToNthOccurrence:(NSUInteger)nth
ofString:(NSString*)string
{
return [self substringToNthOccurrence:nth ofString:string options:0];
}
-(NSString*)substringToNthOccurrence:(NSUInteger)nth
ofString:(NSString*)string
options:(NSStringCompareOptions)options
{
NSUInteger location = 0,
strlength = [string length],
mylength = [self length];
NSRange range = NSMakeRange(location, mylength);
while(nth--)
{
location = [self rangeOfString:string
options:options
range:range].location;
if(location == NSNotFound || (location + strlength) > mylength)
{
return [self copy]; //nth occurrence not found
}
if(nth == 0) strlength = 0; //This prevents the last occurence from being included
range = NSMakeRange(location + strlength, mylength - strlength - location);
}
return [self substringToIndex:location];
}
#end
//main.m
#import "NSString+MyExtension.h"
int main(int argc, char *argv[])
{
#autoreleasepool {
NSString *output = [#"title, price, Camry, $19798, active" substringToNthOccurrence:2 ofString:#","];
NSLog(#"%#", output);
}
}
*I'll leave it as an exercise for someone to implement the mutable versions.
Imagine you have two paths.
http://myserver.com/path1/path2 + /path1/path2/cache/image1.jpg = http://myserver.com/path1/path2/cache/image1.jpg
Both path strings could have more or less path components.
So what I'm asking is how to find the equal part in the strings and then remove that part from one of the strings?
You have no idea whether the "equal" parts are really equal or not. It's not uncommon to have, eg, paths like .../part1/part1/part1/...
For the mechanics of dealing with the paths, though, NSString has some nice methods -- lastPathComponent, stringByAppendindPathComponent, pathComponents, pathWithComponents, etc.
What about this:
- (NSString *)mergeStringsPrefix:(NSString *)prefix suffix:(NSString *)suffix
{
NSString *string = [NSString stringWithFormat:#"%#", prefix];
NSArray *prefixComponents = [prefix pathComponents];
NSArray *suffixComponents = [suffix pathComponents];
if ([prefixComponents count] == 0) return [string retain];
int rootIndex = [suffixComponents indexOfObject:#"/"];
int index = 1;
if (rootIndex == NSNotFound || rootIndex != 0) index = 0;
int startIndex = [prefixComponents indexOfObject:[suffixComponents objectAtIndex:index]];
if (startIndex == NSNotFound) return nil;
if ([suffixComponents count] - index < [prefixComponents count] - startIndex) return nil;
// fing length and check merge compatability
BOOL equalParts = YES;
for (int i=startIndex; i<[prefixComponents count] && equalParts; i++, index++)
{
NSString *el1 = [prefixComponents objectAtIndex:i];
NSString *el2 = [suffixComponents objectAtIndex:index];
if ([el1 compare:el2] != NSOrderedSame) equalParts = NO;
}
if (!equalParts) return nil;
// merge
for (int i=index; i<[suffixComponents count]; i++)
{
string = [string stringByAppendingFormat:#"/%#", [suffixComponents objectAtIndex:i]];
}
return [string retain];
}
This should do for you:
NSString* path1 = #"http://myserver.com/path1/path2";
NSString* path2 = #"/path1/path2/cache/image1.jpg";
NSMutableArray* path1Components = [NSMutableArray arrayWithArray:[path1 componentsSeparatedByString:#"/"]];
NSMutableArray* path2Components = [NSMutableArray arrayWithArray:[path2 componentsSeparatedByString:#"/"]];
[path2Components removeObjectAtIndex:0];
if ([path1Components containsObject:[path2Components objectAtIndex:0]]) {
NSUInteger objectIndex = [path1Components indexOfObject:[path2Components objectAtIndex:0]];
[path1Components removeObjectsInRange:NSMakeRange(objectIndex, [path1Components count]-objectIndex)];
[path1Components addObjectsFromArray:path2Components];
NSString* mergedPath = [path1Components componentsJoinedByString:#"/"];
NSLog(#"%#",mergedPath);
}
I'm developing an iPhone app. I've got a function that reads data from a sqlite database and puts the results into an array. Everything works fine. Here is part of the function that fills the array:
while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
NSString *aVar1 = [NSString stringWithUTF8String(char*)sqlite3_column_text(compiledStatement, 0)];
NSString *aVar2 = [NSString stringWithUTF8String(char*)sqlite3_column_text(compiledStatement, 1)];
NSArray *anArray = [NSArray arrayWithObjects:aVar1,aVar2,nil];
[returnArray addObject:anArray]
[anArray release];
}
//return the array
I want to make this function more generic so that it takes a sql statement string as a parameter, and returns a mutablearray of arrays, no matter how many columns are in the result set.
Is there a way to do this? The solution doesn't have to include arrays -- could be any collection object. I'm just looking for a way to make the function re-usable for other queries to the same database.
Couldn't you just do something like:
int numCols = sqlite3_column_count(compiledStatement);
NSMutableArray *result = [NSMutableArray array];
while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
NSMutableArray *array = [NSMutableArray array];
for (int i = 0; i < numCols; i++) {
[array addObject:
[NSString stringWithUTF8String:
(char *)sqlite3_column_text(compiledStatement, i)]];
}
[result addObject:array];
}
+(NSArray *)executeQueryAndReturnArray:(NSString *)query {
sqlite3_stmt *statement = nil;
const char *sql = [query UTF8String];
if (sqlite3_prepare_v2(database, sql, -1, &statement, NULL) != SQLITE_OK) {
NSLog(#"[SQLITE] Error when preparing query!");
} else {
NSMutableArray *result = [NSMutableArray array];
while (sqlite3_step(statement) == SQLITE_ROW) {
NSMutableArray *row = [NSMutableArray array];
for (int i = 0; i < sqlite3_column_count(statement); i++) {
int colType = sqlite3_column_type(statement, i);
id value;
if (colType == SQLITE_TEXT) {`enter code here`
const unsigned char *col = sqlite3_column_text(statement, i);
value = [NSString stringWithFormat:#"%s", col];
} else if (colType == SQLITE_INTEGER) {
int col = sqlite3_column_int(statement, i);
value = [NSNumber numberWithInt:col];
} else if (colType == SQLITE_FLOAT) {
double col = sqlite3_column_double(statement, i);
value = [NSNumber numberWithDouble:col];
} else if (colType == SQLITE_NULL) {
value = [NSNull null];
} else {
NSLog(#"[SQLITE] UNKNOWN DATATYPE");
}
[row addObject:value];
}
[result addObject:row];
}
return result;
}
return nil;
}