I want to allow only specific characters for a string.
Here's what I've tried.
NSString *mdn = #"010-222-1111";
NSCharacterSet *allowedCharacterSet = [NSCharacterSet characterSetWithCharactersInString:#"+0123456789"];
NSString *trimmed = [mdn stringByTrimmingCharactersInSet:[allowedCharacterSet invertedSet]];
NSString *replaced = [mdn stringByReplacingOccurrencesOfString:#"-" withString:#""];
The result of above code is as below. The result of replaced is what I want.
trimmed : 010-222-1111
replaced : 0102221111
What am I missing here? Why doesn't invertedSet work?
One more weird thing here. If I removed the invertedSet part like
NSString *trimmed = [mdn stringByTrimmingCharactersInSet:allowedCharacterSet];
The result is
trimmed : -222-
I have no idea what makes this result.
stringByTrimmingCharactersInSet: only removes occurrences in the beginning and the end of the string. That´s why when you take inverted set, no feasible characters are found in the beginning and end of the string and thus aren't removed either.
A solution would be:
- (NSString *)stringByRemovingCharacters:(NSString*)str inSet:(NSCharacterSet *)characterSet {
return [[str componentsSeparatedByCharactersInSet:characterSet] componentsJoinedByString:#""];
}
stringByTrimmingCharactersInSet is only removing chars at the end and the beginning of the string, which results in -222-. You have to do a little trick to remove all chars in the set
NSString *newString = [[origString componentsSeparatedByCharactersInSet:
[[NSCharacterSet decimalDigitCharacterSet] invertedSet]]
componentsJoinedByString:#""];
Related
I want to trim the occurence of special characters in a string
String has :
prevs: Case Number
____________________
In this i want to remove -------- this dash from this string .I have tried like this :
NSCharacterSet *trim = [NSCharacterSet characterSetWithCharactersInString:#"-"];
NSString *stringNew = [[previousString2 componentsSeparatedByCharactersInSet:trim] componentsJoinedByString:#""];
Thanks in Advance!
Try This:
NSString *stringWithoutDash = [yourString stringByReplacingOccurrencesOfString:#"-" withString:#""];
NSString *trimedString = [myString stringByReplacingOccurrencesOfString:#"-" withString:#""];
Use regular expression, the pattern [\\s_]{4,} searches for 4 and more whitespace or underscore characters.
NSString *trimmedString = [previousString2 stringByReplacingOccurrencesOfString:#"[\\s_]{4,}" withString:#"" options:NSRegularExpressionSearch range:NSMakeRange(0, previousString2.length)];
If the underscore characters are really dashes reaplace the character in the pattern.
You can use below code to remove your special string.
NSString *yourString = #"This is your string with speical character --------";
NSCharacterSet *removedCharacterSet = [NSCharacterSet characterSetWithCharactersInString:#"--------"];
NSString *finalString = [[yourString componentsSeparatedByCharactersInSet:removedCharacterSet] componentsJoinedByString:#""];
NSLog (#"Your final string : %#", finalString);
I have a string like #"(256) 435-8115" or #"256-435-81-15". I need only the digits (this is a phone number). Is this possible? I haven't found an NSString method to do that.
I think there is much simpler way:
-(NSString*)getNumbersFromString:(NSString*)String{
NSArray* Array = [String componentsSeparatedByCharactersInSet:
[[NSCharacterSet decimalDigitCharacterSet] invertedSet]];
NSString* returnString = [Array componentsJoinedByString:#""];
return (returnString);
}
Input:
NSString *stringWithPhoneNumber=#"(256) 435-8115";
NSArray *plainNumbersArray=
[stringWithPhoneNumber componentsSeparatedByCharactersInSet:
[[NSCharacterSet decimalDigitCharacterSet]invertedSet]];
NSString *plainNumbers = [plainNumbersArray componentsJoinedByString:#""];
NSLog(#"plain number is : %#",plainNumbers);
OutPut:
plain number is : 2564358115
You can use stringByReplacingOccurrencesOfString: withString: to remove characters you don't want such as #"(" with #""
How can I remove leading zeros from an NSString?
e.g. I have:
NSString *myString;
with values such as #"0002060", #"00236" and #"21456".
I want to remove any leading zeros if they occur:
e.g. Convert the previous to #"2060", #"236" and #"21456".
Thanks.
For smaller numbers:
NSString *str = #"000123";
NSString *clean = [NSString stringWithFormat:#"%d", [str intValue]];
For numbers exceeding int32 range:
NSString *str = #"100004378121454";
NSString *clean = [NSString stringWithFormat:#"%d", [str longLongValue]];
This is actually a case that is perfectly suited for regular expressions:
NSString *str = #"00000123";
NSString *cleaned = [str stringByReplacingOccurrencesOfString:#"^0+"
withString:#""
options:NSRegularExpressionSearch
range:NSMakeRange(0, str.length)];
Only one line of code (in a logical sense, line breaks added for clarity) and there are no limits on the number of characters it handles.
A brief explanation of the regular expression pattern:
The ^ means that the pattern should be anchored to the beginning of the string. We need that to ensure it doesn't match legitimate zeroes inside the sequence of digits.
The 0+ part means that it should match one or more zeroes.
Put together, it matches a sequence of one or more zeroes at the beginning of the string, then replaces that with an empty string - i.e., it deletes the leading zeroes.
The following method also gives the output.
NSString *test = #"0005603235644056";
// Skip leading zeros
NSScanner *scanner = [NSScanner scannerWithString:test];
NSCharacterSet *zeros = [NSCharacterSet
characterSetWithCharactersInString:#"0"];
[scanner scanCharactersFromSet:zeros intoString:NULL];
// Get the rest of the string and log it
NSString *result = [test substringFromIndex:[scanner scanLocation]];
NSLog(#"%# reduced to %#", test, result);
- (NSString *) removeLeadingZeros:(NSString *)Instring
{
NSString *str2 =Instring ;
for (int index=0; index<[str2 length]; index++)
{
if([str2 hasPrefix:#"0"])
str2 =[str2 substringFromIndex:1];
else
break;
}
return str2;
}
In addition to adali's answer, you can do the following if you're worried about the string being too long (i.e. greater than 9 characters):
NSString *str = #"000200001111111";
NSString *strippedStr = [NSString stringWithFormat:#"%lld", [temp longLongValue]];
This will give you the result: 200001111111
Otherwise, [NSString stringWithFormat:#"%d", [temp intValue]] will probably return 2147483647 because of overflow.
I have a set of NSString representing the names of the files in a directory. These names are structured this way:
XXXXXXXXX_YYYY_AAAA.ext
All the sections separated by "_" are of variable length and I would only have the first.
How can I separate the first part from the other?
Find the position of the '_' character, then get a substring 0 through that position. Note that substringToIndex: does not include the character at the index position.
NSRange r = [myString rangeOfString:#"_"];
NSString *res = [myString substringToIndex:r.location];
Take a look at the NSString method componentsSeparatedByString:. That will tokenize a string and return you an array. Something like this:
NSArray *array = [#"XXXXXXXXX_YYYY_AAAA.ext" componentsSeparatedByString:#"_"];
NSString *firstToken = [array objectAtIndex:0];
NSArray *array = [yourString componentsSeparatedByString:#"_"];
NSString *Xs = [array objectAtIndex:0];
Try componentsSeparatedByString: under the heading Dividing Strings.
NSString Docs
I've got some trouble 'ere trying to remove the last character of an NSString.
I'm kinda newbie in Objective-C and I have no idea how to make this work.
Could you guys light me up?
NSString *newString = [oldString substringToIndex:[oldString length]-1];
Always refer to the documentation:
substringToIndex:
length
To include code relevant to your case:
NSString *str = textField.text;
NSString *truncatedString = [str substringToIndex:[str length]-1];
Try this:
s = [s substringToIndex:[s length] - 1];
NSString *string = [NSString stringWithString:#"ABCDEF"];
NSString *newString = [string substringToIndex:[string length]-1];
NSLog(#"%#",newString);
You can see = ABCDE
NSString = *string = #"abcdef";
string = [string substringToIndex:string.length-(string.length>0)];
If there is a character to delete (i.e. the length of the string is greater than 0)
(string.length>0) returns 1, thus making the code return:
string = [string substringToIndex:string.length-1];
If there is NOT a character to delete (i.e. the length of the string is NOT greater than 0)
(string.length>0) returns 0, thus making the code return:
string = [string substringToIndex:string.length-0];
which prevents crashes.
This code will just return the last character of the string and not removing it :
NSString *newString = [oldString substringToIndex:[oldString length]-1];
you may use this instead to remove the last character and retain the remaining values of a string :
str = [str substringWithRange:NSMakeRange(0,[str length] - 1)];
and also using substringToIndex to a NSString with 0 length will result to crashes.
you should add validation before doing so, like this :
if ([str length] > 0) {
str = [str substringToIndex:[s length] - 1];
}
with this, it is safe to use substring method.
NOTE : Apple will reject your application if it is vulnerable to crashes.
Simple and Best Approach
[mutableString deleteCharactersInRange:NSMakeRange([myRequestString length]-1, 1)];