Check if word is in string and replace the string - ios

I need a method to check if the [msg valueForKey:#"text"] contain the currentString and if it does it should be replace with the character * depending on the length of the word.
How can I do this? The code below is how far I've come:
NSDictionary *msg = [self.messages objectAtIndex:indexPath.row];
for (NSString *currentString in badwords)
{
if ([[msg valueForKey:#"text"]]) {
}
}

You can use the stringByReplacingOccurrencesOfString method:
NSString *newString = [oldString stringByReplacingOccurrencesOfString:currentString
withString:replacementString];
You would create the replacement string like this:
NSMutableString *replacementString = [[NSMutableString alloc] init];
for (int i = 0; i < currentString.length; i++)
{
[replacementString appendString:#"*"];
}

You should read the NSString class reference. There are a whole family of methods supporting this sort of thing. For your specific need, look at methods like rangeOfString: or stringByReplacingOccurrencesOfString:withString:

How about this:
NSDictionary *msg = [self.messages objectAtIndex:indexPath.row];
NSString *redactedString = [msg valueForKey:#"text"];
for (NSString *currentString in badwords)
redactedString = [redactedString stringByReplacingOccurrencesOfString:currentString
withString:#"*"];
NSLog(redactedString);
Adapted from #reecon.

I found an github project which helped to achieve this. I hope someone else can use this.
https://github.com/IslandOfDoom/IODProfanityFilter

Related

How to query an NSDictionary using an expression written in NSString?

I want to be able to run the following hypothetical function called evaluateExpression:on: and get "John" as answer.
NSDictionary *dict = #{"result": #[#{#"name": #"John"}, #{#"name": #"Mary"}]};
NSString *expression = #"response['result'][0]['name']";
NSString *answer = [self evaluateExpression: expression on: dict];
Is this possible?
There's an NSObject category that extends valueForKeyPath to give valueForKeyPathWithIndexes. It lets you write this:
NSDictionary *dict = #{#"result": #[#{#"name": #"John"}, #{#"name": #"Mary"}]};
NSString *path = #"result[0].name";
NSString *answer = [dict valueForKeyPathWithIndexes:path];
XCTAssertEqualStrings(answer, #"John");
The category is by psy, here: Getting array elements with valueForKeyPath
#interface NSObject (ValueForKeyPathWithIndexes)
-(id)valueForKeyPathWithIndexes:(NSString*)fullPath;
#end
#import "NSObject+ValueForKeyPathWithIndexes.h"
#implementation NSObject (ValueForKeyPathWithIndexes)
-(id)valueForKeyPathWithIndexes:(NSString*)fullPath
{
NSRange testrange = [fullPath rangeOfString:#"["];
if (testrange.location == NSNotFound)
return [self valueForKeyPath:fullPath];
NSArray* parts = [fullPath componentsSeparatedByString:#"."];
id currentObj = self;
for (NSString* part in parts)
{
NSRange range1 = [part rangeOfString:#"["];
if (range1.location == NSNotFound)
{
currentObj = [currentObj valueForKey:part];
}
else
{
NSString* arrayKey = [part substringToIndex:range1.location];
int index = [[[part substringToIndex:part.length-1] substringFromIndex:range1.location+1] intValue];
currentObj = [[currentObj valueForKey:arrayKey] objectAtIndex:index];
}
}
return currentObj;
}
#end
Plain old valueForKeyPath will get you close, but not exactly what you asked for. It may be useful in this form though:
NSDictionary *dict = #{#"result": #[#{#"name": #"John"}, #{#"name": #"Mary"}]};
NSString *path = #"result.name";
NSString *answer = [dict valueForKeyPath:path];
XCTAssertEqualObjects(answer, (#[#"John", #"Mary"]));
After spending quite a while trying to tackle this problem in the most efficient way, here's another take I came up with: Use javascript.
The above approach posted by Ewan definitely takes care of the problem, but I had some additional custom features I wanted to add, and objective-c approach became too complex very quickly. I ended up writing eval code in javascript and integrating it into objective-c using JavascriptCore. With that, it becomes as simple as one line of eval() call.

How to remove conflicting return type?

I am dividing string and and storing it in splitArray and want to return it.
But I am getting conflicting array on the first line
- (NSArray *)subdividingString:(NSString *)string {
NSArray *splitArray = [string componentsSeparatedByString:#" "];
return splitArray;
}
First: there is nothing wrong with the code, but you are most likely having another issue (e.g. where you call subdividingString:).
Second: You shouldn't introduce a method that is exactly doing what another one is doing already. Just use
NSString *mystring = #"some string";
NSArray *chunks = [mystring componentsSeparatedByString:#" "];

Split NSString from first whitespace

I have a name textfield in my app, where both the firstname maybe a middle and a lastname is written. Now I want to split these components by the first whitespace, the space between the firstname and the middlename/lastname, so I can put it into my model.
For example:
Textfield Text: John D. Sowers
String 1: John
String 2: D. Sowers.
I have tried using [[self componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] firstObject]; & [[self componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] lastObject];
But these only work if have a name without a middlename. Since it gets the first and the last object, and the middlename is ignored.
So how would I manage to accomplish what I want?
/*fullNameString is an NSString*/
NSRange rangeOfSpace = [fullNameString rangeOfString:#" "];
NSString *first = rangeOfSpace.location == NSNotFound ? fullNameString : [fullNameString substringToIndex:rangeOfSpace.location];
NSString *last = rangeOfSpace.location == NSNotFound ? nil :[fullNameString substringFromIndex:rangeOfSpace.location + 1];
...the conditional assignment (rangeOfSpace.location == NSNotFound ? <<default value>> : <<real first/last name>>) protects against an index out of bounds error.
Well that method is giving you an array with all the words split by white space, so then you can grab the first object as the first name and the rest of the objects as middle/last/etc
NSArray *ar = [self componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
NSString *firstName = [ar firstObject];
NSMutableString *rest = [[NSMutableString alloc] init];
for(int i = 1; i < ar.count; i++)
{
[rest appendString:[ar objectAtIndex:i]];
[rest appendString:#" "];
}
//now first name has the first name
//rest has the rest
There might be easier way to do this, but this is one way..
Hope it helps
Daniel
I think this example below I did, solves your problem.
Remember you can assign values from the array directly, without transforming into string.
Here is an example:
NSString *textField = #"John D. Sowers";
NSArray *fullName = [textField componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:#" "]];
if (fullName.count)
{
if (fullName.count > 2)
{
NSLog(#"Array has more than 2 objects");
NSString *name = fullName[0];
NSLog(#"Name:%#",name);
NSString *middleName = fullName[1];
NSLog(#"Middle Name:%#",middleName);
NSString *lastName = fullName[2];
NSLog(#"Last Name:%#",lastName);
}
else if(fullName.count == 2)
{
NSLog(#"Array has 2 objects");
NSString *name = fullName[0];
NSLog(#"Name:%#",name);
NSString *lastName = fullName[1];
NSLog(#"Last Name:%#",lastName);
}
else
{
NSString *name = fullName[0];
}
}
I found this to be most robust:
NSString *fullNameString = #"\n Barnaby Marmaduke \n \n Aloysius ";
NSMutableArray *nameArray = [[fullNameString componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] mutableCopy];
[nameArray removeObject:#""];
NSString *firstName = [nameArray firstObject];
if(nameArray.count)
{
[nameArray removeObjectAtIndex:0];
}
NSString *nameRemainder = [nameArray componentsJoinedByString:#" "];
Bob's your uncle.

Replace String Between Two Strings

I have a serious problem about indexing in array. I've been working on this for 2 days and couldn't find answer yet.
I want to do that, search specific character in array then replace it with other string. I'm using replaceObjectAtIndex method but my code is doesn't work.
Here is my code;
NSString *commentText = commentTextView.text;
NSUInteger textLength = [commentText length];
NSString *atSign = #"#";
NSMutableArray *commentArray = [[NSMutableArray alloc] init];
[commentArray addObject:commentText];
for (int arrayCounter=1; arrayCounter<=textLength; arrayCounter++)
{
NSRange isRange = [commentText rangeOfString:atSign options:NSCaseInsensitiveSearch];
if(isRange.location != NSNotFound)
{
commentText = [commentText stringByReplacingOccurrencesOfString:commentText withString:atSign];
[_mentionsearch filtrele:_mentionText];
id<textSearchProtocol> delegate;
[delegate closeList:[[self.searchResult valueForKey:#"user_name"] objectAtIndex:indexPath.row]];
}
}
Ok, now i can find "#" sign in the text and i can match it. But this is the source of problem that, i can not replace any string with "#" sign. Here is the last part of code;
-(void)closeList
{
NSArray *arrayWithSign = [commentTextView.text componentsSeparatedByString:#" "];
NSMutableArray *arrayCopy = [arrayWithSign mutableCopy];
[arrayCopy replaceObjectAtIndex:isRange.location withObject:[NSString stringWithFormat:#"#%#",username]];
}
When im logging isRange.location value, it returns correct. But when im try to run, my application is crashing. So, i can not replacing [NSString stringWithFormat:#"#%#",username] parameter. How can i solve this problem?
If I understand correctly you want to change a substring in a string with a new string. In this case, why don't you use directly the stringByReplacingOccurrencesOfString method of NSString:
NSString *stringToBeChanged = #"...";
NSString *stringToBeChangedWith = #"...";
NSString *commentTextNew = [commentText stringByReplacingOccurrencesOfString:stringToBeChanged withString:stringToBeChangedWith];

Create string based on characters expected

I would like to create a string based on the number of characters passed in. Each character passed in will be a "X". So for example, if the length passed in is 5, then the string created should be
NSString *testString=#"XXXXX";
if it is 2 then it would be
NSString *testString=#"XX";
Can anyone tell me what the most efficient way to do this would be?
Thank you!
If you know the maximum length is some reasonable number then you could do something simple like this:
- (NSString *)xString:(NSUInteger)length {
static NSString *xs = #"XXXXXXXXXXXXXXXXXXXXXXXXXXX";
return [xs substringToIndex:length];
}
NSString *str = [self xString:5]; // str will be #"XXXXX";
If you pass in too large of a length, the app will crash - add more Xs to xs.
This approach is more efficient than building up an NSMutableString but it does make an assumption about the maximum length you might need.
- (NSString *)stringOf:(NSString *)str times:(NSInteger)count
{
NSMutableString *targ = [[NSMutableString alloc] initWithCapacity:count];
for (int i=0; i < count; i++)
{
[targ appendString:str];
}
return targ;
}
and
[self stringOf:#"X" times:4];
note that initWithCapacity: (in performance manner) better than init. But I guess that's all for efficiency.
The way I would do it is
NSMutableString *xString = [[NSMutableString alloc] init];
while ( int i = 0; i < testString.length; i++ ) {
[xString appendString:#"X"];
i++;
}
NSUInteger aLength. // assume this is the argument
NSMutableString *xStr = [NSMutableString stringWithCapacity: aLength];
for ( NSUInteger i = 0; i < aLength; i++ ) {
[xStr appendFormat:#"X"];
}
The following will do what you ask in one call:
NSString *result = [#"" stringByPaddingToLength:numberOfCharsWanted
withString:characterToRepeat
startingAtIndex:0];
where numberOfCharsWanted is an NSUInteger and characterToRepeat is an NSString containing the character.

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