how to add comma to string after every nth character in xcode - iphone

Question

my problem is pretty simple. I assign a value to string variable in xcode which looks like this:
ARAMAUBEBABRBGCNDKDEEEFO
and I need it like this:
AR,AM,AU,BE,BA,BR,BG,CN,DK,DE,EE,FO
The length is different in each variable.
thanx in advance

Answer 1

This function is usefull for numbers that need coma every thousands... which is what I wanted, hope it helps.
//add comas to a a string...
//example1: #"5123" = #"5,123"
//example2: #"123" = #"123"
//example3: #"123123123" = #"123,123,123"
-(NSString*) addComasToStringEvery3chrsFromRightToLeft:(NSString*) myString{
NSMutableString *stringFormatted = [NSMutableString stringWithFormat:#"%#",myString];
for(NSInteger i=[stringFormatted length]-3;i>0;i=i-3) {
if (i>0) {
[stringFormatted insertString: #"," atIndex: i];
}
}
return stringFormatted;
}

Answer 2

Try this:
int num;
NSMutableString *string1 = [NSMutableString stringWithString: #"1234567890"];
num = [string1 length];
for(int i=3;i<=num+1;i++) {
[string1 insertString: #"," atIndex: i];
i+=3;
}

Answer 3

NSString *yourString; // the string you want to process
int len = 2; // the length
NSMutableString *str = [NSMutableString string];
int i = 0;
for (; i < [yourString length]; i+=len) {
NSRange range = NSMakeRange(i, len);
[str appendString:[yourString substringWithRange:range]];
[str appendString:#","];
}
if (i < [str length]-1) { // add remain part
[str appendString:[yourString substringFromIndex:i]];
}
// str now is what your want

Answer 4

This would work well when your string is not very large:
NSString * StringByInsertingStringEveryNCharacters(NSString * const pString,
NSString * const pStringToInsert,
const size_t n) {
NSMutableString * const s = pString.mutableCopy;
for (NSUInteger pos = n, advance = n + pStringToInsert.length; pos < s.length; pos += advance) {
[s insertString:pStringToInsert atIndex:pos];
}
return s.copy;
}
If the string is very large, you should favor to compose it without insertion (append-only).
(define your own error detection)