How can I search a string url for a string value?
String url:
http://localHost:8070/serviceCase=ActiveService
http://localHost:8070/serviceCase=KoplService
String Value is:
ActiveService
I need to print the urls that do have "ActiveService"!
You could probably do something like this(if your url really is a string):
if ([url rangeOfString:value].location == NSNotFound){
dosomething
} else {
doSomethingElse
}
NSString *url = #"http://localHost:8070/serviceCase=ActiveService";
if ([url rangeOfString:#"ActiveService"].location != NSNotFound) {
NSLog(#"URL has the string");
}
I recommend below NSString Category.
NSString+Extend.h
#import <Foundation/Foundation.h>
#interface NSString (Extend)
- (BOOL)containsString:(NSString *)aString ignoringCase:(BOOL)flag;
- (BOOL)containsString:(NSString *)aString;
#end
NSString+Extend.m
#import "NSString+Extend.h"
#implementation NSString (Extend)
- (BOOL)containsString:(NSString *)aString
{
return [self containsString:aString ignoringCase:NO];
}
- (BOOL)containsString:(NSString *)aString ignoringCase:(BOOL)flag
{
unsigned mask = (flag ? NSCaseInsensitiveSearch : 0);
return [self rangeOfString:aString options:mask].length > 0;
}
#end
#import "NSString+Extend.h"
NSString *url = #"http://localHost:8070/serviceCase=ActiveService";
NSString *findString = #"ActiveService";
BOOL isContains = [url containsString:findString];
if(isContains)
{
//do stuff
}
else
{
//do stuff
}
if([string hasSuffix:#"ActiveService"]) {
// Do your stuff
}
I need to remove all emoijs from a NSString.
So far i am using this NSString extension ...
- (NSString*)noEmoticon {
static NSMutableCharacterSet *emoij = NULL;
if (emoij == NULL) {
emoij = [[NSMutableCharacterSet alloc] init];
// unicode range of old emoijs
[emoij removeCharactersInRange:NSMakeRange(0xE000, 0xE537 - 0xE000)];
}
NSRange range = [self rangeOfCharacterFromSet:emoij];
if (range.length == 0) {
return self;
}
NSMutableString *cleanedString = [self mutableCopy];
while (range.length > 0) {
[cleanedString deleteCharactersInRange:range];
range = [cleanedString rangeOfCharacterFromSet:emoij];
}
return cleanedString;
}
... but that does not work at all. The range.length is always 0.
So the general question is : How can i remove a range of unicode characters from a NSString?
Thanks a lot.
It seems to me that in the above code the emoij variable is eventually an empty set. Didn't you mean to addCharactersInRange: rather than to removeCharactersInRange:?
I need to match my string in this way: *myString*
where * mean any substring.
which method should I use?
can you help me, please?
If it's for iPhone OS 3.2 or later, use NSRegularExpressionSearch.
NSString *regEx = [NSString stringWithFormat:#".*%#.*", yourSearchString];
NSRange range = [stringToSearch rangeOfString:regEx options:NSRegularExpressionSearch];
if (range.location != NSNotFound) {
}
You can't do an actual search using a * (wildcard character), but you can usually do something that is equivalent:
Equivalent to searching for theTerm*:
if ([theString hasPrefix:#"theTerm"]) {
Equivalent to searching for *theTerm:
if ([theString hasSuffix:#"theTerm"]) {
Or, using the category on NSString shown below, the following is equivalent to searching for *theTerm*:
if ([theString containsString:#"theTerm"]) {
A category is simply a new method (like a function) that we add to class. I wrote the following one because it generally makes more sense to me to think of one string containing another rather than dealing with NSRanges.
// category on NSString
#interface NSString (MDSearchAdditions)
- (BOOL)containsString:(NSString *)aString;
#end
#implementation NSString (MDSearchAdditions)
- (BOOL)containsString:(NSString *)aString {
return [self rangeOfString:aString].location != NSNotFound;
}
#end
If you need something more evolved, try https://github.com/dblock/objc-ngram.
I want to ask a question about the objective C. Does the NSString * contains some functions to check the NSString * contains some string in the UITextField.text? For example
NSString *checkString = #"abcd%"
if(checkString contains '%') // I want this function
return YES;
else
return NO;
if([checkString rangeOfString:#"%"].location != NSNotFound)
// hooray!
You can use - (NSRange)rangeOfString:(NSString *)aString. The code will look something like:
NSRange range = [UITextField.text rangeOfString:#"!"];
if (range.length > 0){
NSLog(#"String contains '!'");
}
else {
NSLog(#"No '!' found in string");
}
The code from the previous post is not correct
NSRange range = [UITextField.text rangeOfString:#"!"];
if (range.length >= 0){
NSLog(#"String contains '!'");
}
else {
NSLog(#"No '!' found in string");
}
It should be "range.length > 0"
How do you test if an NSString is empty? or all whitespace or nil? with a single method call?
You can try something like this:
#implementation NSString (JRAdditions)
+ (BOOL)isStringEmpty:(NSString *)string {
if([string length] == 0) { //string is empty or nil
return YES;
}
if(![[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length]) {
//string is all whitespace
return YES;
}
return NO;
}
#end
Check out the NSString reference on ADC.
This is what I use, an Extension to NSString:
+ (BOOL)isEmptyString:(NSString *)string;
// Returns YES if the string is nil or equal to #""
{
// Note that [string length] == 0 can be false when [string isEqualToString:#""] is true, because these are Unicode strings.
if (((NSNull *) string == [NSNull null]) || (string == nil) ) {
return YES;
}
string = [string stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
if ([string isEqualToString:#""]) {
return YES;
}
return NO;
}
I use,
+ (BOOL ) stringIsEmpty:(NSString *) aString {
if ((NSNull *) aString == [NSNull null]) {
return YES;
}
if (aString == nil) {
return YES;
} else if ([aString length] == 0) {
return YES;
} else {
aString = [aString stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
if ([aString length] == 0) {
return YES;
}
}
return NO;
}
+ (BOOL ) stringIsEmpty:(NSString *) aString shouldCleanWhiteSpace:(BOOL)cleanWhileSpace {
if ((NSNull *) aString == [NSNull null]) {
return YES;
}
if (aString == nil) {
return YES;
} else if ([aString length] == 0) {
return YES;
}
if (cleanWhileSpace) {
aString = [aString stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
if ([aString length] == 0) {
return YES;
}
}
return NO;
}
I hate to throw another log on this exceptionally old fire, but I'm leery about editing someone else's answer - especially when it's the selected answer.
Jacob asked a follow up question: How can I do this with a single method call?
The answer is, by creating a category - which basically extends the functionality of a base Objective-C class - and writing a "shorthand" method for all the other code.
However, technically, a string with white space characters is not empty - it just doesn't contain any visible glyphs (for the last couple of years I've been using a method called isEmptyString: and converted today after reading this question, answer, and comment set).
To create a category go to Option+Click -> New File... (or File -> New -> File... or just command+n) -> choose Objective-C Category. Pick a name for the category (this will help namespace it and reduce possible future conflicts) - choose NSString from the "Category on" drop down - save the file somewhere. (Note: The file will automatically be named NSString+YourCategoryName.h and .m.)
I personally appreciate the self-documenting nature of Objective-C; therefore, I have created the following category method on NSString modifying my original isEmptyString: method and opting for a more aptly declared method (I trust the compiler to compress the code later - maybe a little too much).
Header (.h):
#import <Foundation/Foundation.h>
#interface NSString (YourCategoryName)
/*! Strips the string of white space characters (inlcuding new line characters).
#param string NSString object to be tested - if passed nil or #"" return will
be negative
#return BOOL if modified string length is greater than 0, returns YES;
otherwise, returns NO */
+ (BOOL)visibleGlyphsExistInString:(NSString *)string;
#end
Implementation (.m):
#implementation NSString (YourCategoryName)
+ (BOOL)visibleGlyphsExistInString:(NSString *)string
{
// copying string should ensure retain count does not increase
// it was a recommendation I saw somewhere (I think on stack),
// made sense, but not sure if still necessary/recommended with ARC
NSString *copy = [string copy];
// assume the string has visible glyphs
BOOL visibleGlyphsExist = YES;
if (
copy == nil
|| copy.length == 0
|| [[copy stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length] == 0
) {
// if the string is nil, no visible characters would exist
// if the string length is 0, no visible characters would exist
// and, of course, if the length after stripping the white space
// is 0, the string contains no visible glyphs
visibleGlyphsExist = NO;
}
return visibleGlyphsExist;
}
#end
To call the method be sure to #import the NSString+MyCategoryName.h file into the .h or .m (I prefer the .m for categories) class where you are running this sort of validation and do the following:
NSString* myString = #""; // or nil, or tabs, or spaces, or something else
BOOL hasGlyphs = [NSString visibleGlyphsExistInString:myString];
Hopefully that covers all the bases. I remember when I first started developing for Objective-C the category thing was one of those "huh?" ordeals for me - but now I use them quite a bit to increase reusability.
Edit: And I suppose, technically, if we're stripping characters, this:
[[copy stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length] == 0
Is really all that is needed (it should do everything that category method does, including the copy), but I could be wrong on that score.
I'm using this define as it works with nil strings as well as empty strings:
#define STR_EMPTY(str) \
str.length == 0
Actually now its like this:
#define STR_EMPTY(str) \
(![str isKindOfClass:[NSString class]] || str.length == 0)
Maybe you can try something like this:
+ (BOOL)stringIsEmpty:(NSString *)str
{
return (str == nil) || (([str stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]).length == 0);
}
Based on the Jacob Relkin answer and Jonathan comment:
#implementation TextUtils
+ (BOOL)isEmpty:(NSString*) string {
if([string length] == 0 || ![[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length]) {
return YES;
}
return NO;
}
#end
Should be easier:
if (![[string stringByReplacingOccurencesOfString:#" " withString:#""] length]) { NSLog(#"This string is empty"); }