How to detect if UISearchBar contains only blank spaces not any other character or string and replace it with #""?
You can trim the string with a character set containing whitespace using the NSString stringByTrimmingCharactersInSet message (using the whitespaceCharacterSet):
NSString * searchString = [searchBar.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
if (![searchString length])
// return ... search bar was just whitespace
You can check as
[yourSearchBar.text isEqualToString:#""]
Hope it helps.
if([searchBar.text isEqualToString:#""] && [searchBar.text length] ==0){
// Blank Space in searchbar
else{
// Do Search
}
Use isEqualToString method of NSString
Use stringByTrimmingCharactersInSet to trim the character from NSString.
- (NSString *)stringByTrimmingCharactersInSet:(NSCharacterSet *)set
Use as below.
NSString* myString = mySearchBar.text
myString = [myString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
Here's how you detect and replace it: (assuming the UISearchField is called searchBar)
NSString*replacement;
if ([searchBar.text isEqualToString:#" "])
{
replacement = [NSString stringByReplacingOccurancesOfString:#" " withString:#""];
}
searchBar.text = replacement;
Have a look in the Apple Documentation for NSString for more.
Edit:
If you have more than once space, do this:
NSString *s = [someString stringByReplacingOccurrencesOfString:#" "
withString:#""
options:NSRegularExpressionSearch
range:NSMakeRange(0, [someString length])
];
searchBar.text = s;
This worked for me: if you are using #"" or length already to control say a button then this version really does detect the whitespace, if a space has been entered...
if([activeField.text isEqualToString:#" "] && [activeField.text length] ==1){
// Blank Space in searchbar
{
// an alert example
}
Related
How to check whether a string contains whitespaces in between characters?
use rangeOfCharactersFromSet:
NSString *foo = #"HALLO WELT";
NSRange whiteSpaceRange = [foo rangeOfCharacterFromSet:[NSCharacterSet whitespaceCharacterSet]];
if (whiteSpaceRange.location != NSNotFound) {
NSLog(#"Found whitespace");
}
note: this will also find whitespace at the beginning or end of the string. If you don't want this trim the string first...
NSString *trimmedString = [foo stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
NSRange whiteSpaceRange = [trimmedString rangeOfCharacterFromSet:[NSCharacterSet whitespaceCharacterSet]];
You can also follow these steps:
NSArray *componentsSeparatedByWhiteSpace = [testString componentsSeparatedByString:#" "];
If there is any whitespace in your string, then it will separate those and store different components in the array. Now you need to take the count of array. If count is greater than 1, it means there are two components, i.e, presence of white space.
if([componentsSeparatedByWhiteSpace count] > 1){
NSLog(#"Found whitespace");
}
I have a string that contains words with consonants and vowels. How can I extract only consonants from the string?
NSString *str = #"consonants.";
Result must be:
cnsnnts
You could make a character set with all the vowels (#"aeiouy")
+ (id)characterSetWithCharactersInString:(NSString *)aString
then use the
- (NSString *)stringByTrimmingCharactersInSet:(NSCharacterSet *)set
method.
EDIT: This will only remove vowels at the beginning and end of the string as pointed out in the other post, what you could do instead is use
- (NSArray *)componentsSeparatedByCharactersInSet:(NSCharacterSet *)separator
then stick the components back together. You may also need to include capitalized versions of the vowels in the set, and if you want to also deal with accents (à á è è ê ì etc...) you'll probably have to include that also.
Unfortunately stringByTrimmingCharactersInSet wont work as it only trim leading and ending characters, but you could try using a regular expression and substitution like this:
[[NSRegularExpression
regularExpressionWithPattern:#"[^bcdefghjklmnpqrstvwx]"
options:NSRegularExpressionCaseInsensitive
error:NULL]
stringByReplacingMatchesInString:str
options:0
range:NSMakeRange(0, [str length])
withTemplate:#""]
You probably want to tune the regex and options for your needs.
Possible, for sure not-optimal, solution. I'm printing intermediate results for your learning. Take care of memory allocation (I didn't care). Hopefully someone will send you a better solution, but you can copy and paste this for the moment.
NSString *test = #"Try to get all consonants";
NSMutableString *found = [[NSMutableString alloc] init];
NSInteger loc = 0;
NSCharacterSet *consonants = [NSCharacterSet characterSetWithCharactersInString:#"bcdfghjklmnpqrstvwxyz"];
while(loc!=NSNotFound && loc<[test length]) {
NSRange r = [[test lowercaseString] rangeOfCharacterFromSet:consonants options:0 range:NSMakeRange(loc, [test length]-loc)];
if(r.location!=NSNotFound) {
NSString *temp = [test substringWithRange:r];
NSLog(#"Range: %# Temp: %#",NSStringFromRange(r), temp);
[found appendString:temp];
loc=r.location+r.length;
} else {
loc=NSNotFound;
}
}
NSLog(#"Found: %#",found);
Here is a NSString category that does the job:
- (NSString *)consonants
{
NSString *result = [NSString stringWithString:self];
NSCharacterSet *characterSet = [NSCharacterSet characterSetWithCharactersInString:#"aeiou"];
while(1)
{
NSRange range = [result rangeOfCharacterFromSet:characterSet options:NSCaseInsensitiveSearch];
if(range.location == NSNotFound)
break;
result = [result stringByReplacingCharactersInRange:range withString:#""];
}
return result;
}
I want user to not use any extra spaces in the text field. How to do that?
Description : I have a text field which I am using for "Title of Something". I don't want to allow any user to give extra spaces/only spaces.
Regards
Here small snippet for UITextFieldDelegate:
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if([[textField text] length] > 0) {
if([[textField text] characterAtIndex:([[textField text] length]-1)] == ' ' &&
[string isEqualToString:#" "]) return NO;
}
return YES;
}
You can trim the string when received:
NSString *string = #" spaces in front and at the end ";
NSString *trimmedString = [string stringByTrimmingCharactersInSet:
[NSCharacterSet whitespaceAndNewlineCharacterSet]];
NSLog(trimmedString)
Also if you want to remove any double spaces inside the string i think this would do the trick:
NSString *noSpaces = [[string componentsSeparatedByCharactersInSet: [NSCharacterSet whitespaceCharacterSet]] componentsJoinedByString: #" "];
just try this
NSString *t1= [txt.text stringByReplacingOccurrencesOfString:#" " withString:#""]
I have a string say "Allentown, pa"
How to remove the white space in between , and pa using objective c?
This will remove all space from myString.
NSString *newString = [myString stringByReplacingOccurrencesOfString:#" " withString:#""];
Here is a proper and documented way of removing white spaces from your string.
whitespaceCharacterSet Apple Documentation for iOS says:
Returns a character set containing only the in-line whitespace characters space (U+0020) and tab (U+0009).
+ (id)whitespaceCharacterSet
Return Value
A character set containing only the in-line whitespace characters space (U+0020) and tab (U+0009).
Discussion
This set doesn’t contain the newline or carriage return characters.
Availability
Available in iOS 2.0 and later.
You can use this documented way:
[yourString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
Hope this helps you.
If you need any more help then please let me know on this.
Probably the solution in one of the answers in Collapse sequences of white space into a single character and trim string:
NSString *whitespaceString = #" String with whitespaces ";
NSString *trimmedString = [whitespaceString stringByReplacingOccurrencesOfString:#" " withString:#""];
If you want to white-space and new-line character as well then use "whitespaceAndNewlineCharacterSet" instead of "whitespaceCharacterSet"
NSCharacterSet *whitespace = [NSCharacterSet whitespaceCharacterSet];
NSString *trimmedString = [temp.text stringByTrimmingCharactersInSet:whitespace];
NSLog(#"Value of the text field is %#",trimmedString);
myStr = [myStr stringByReplacingOccurrencesOfString:#" " withString:#""];
NSString *sample = #" string with whitespaces";
NSString *escapeWhiteSpaces = [sample stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
- (NSString *)removeWhitespaces {
return [[self componentsSeparatedByCharactersInSet:
[NSCharacterSet whitespaceCharacterSet]]
componentsJoinedByString:#""];
}
In my case NSString was added Zero Width Space(i i used some library). so solution worked for me.
NSMutableString *newString=[[newString stringByReplacingOccurrencesOfString:#"\u200B" withString:#""] mutableCopy];
#"\u200B" is Zero width space character value.
Here is the proper way to remove extra whitespaces from string which is coming in between.
NSString *yourString = #"Allentown, pa";
NSCharacterSet *whitespaces = [NSCharacterSet whitespaceCharacterSet];
NSPredicate *noEmptyStrings = [NSPredicate predicateWithFormat:#"SELF != ''"];
NSArray *parts = [yourString componentsSeparatedByCharactersInSet:whitespaces];
NSArray *filteredArray = [parts filteredArrayUsingPredicate:noEmptyStrings];
yourString = [filteredArray componentsJoinedByString:#" "];
you can use remove function to remove any substring from the string
- (NSString*)remove:(NSString*)textToRemove fromString:(NSString*)input {
return [input stringByReplacingOccurrencesOfString:textToRemove withString:#""];
}
I have tried all the solutions here, none of them could remove the whitespace generated by the Chinese PinYin Input method.
After some debugging, I found this working:
NSString *newString = [myString stringByReplacingOccurrencesOfString:#"\342\200\206" withString:#""];
I have googled what the '\342\200\206' is, but failed.
Whatever, it works for me.
Hi there is the swift version of the solution with extension :
extension String{
func deleteSpaces() -> String{
return self.stringByReplacingOccurrencesOfString(" ", withString: "")
}
}
And Just call
(yourString as! String).deleteSpaces()
Swift 3:
var word: String = "Hello world"
let removeWhiteSpace = word.stringByRemovingWhitespaces
word = "Helloworld"
is there a simple way to remove the extra spaces in a string? ie like...
NSString *str = #"this string has extra empty spaces";
result should be:
NSString *str = #"this string has extra empty spaces";
Thanks!
replace all double space with a single space until there are no more double spaces in your string.
- (NSString *)stripDoubleSpaceFrom:(NSString *)str {
while ([str rangeOfString:#" "].location != NSNotFound) {
str = [str stringByReplacingOccurrencesOfString:#" " withString:#" "];
}
return str;
}