Case insensitive comparison NSString

Question

Can anyone point me to any resources about case insensitive comparison in Objective C? It doesn\'t seem to have an equivalent method to str1.equalsIgnoreCase(str2)

Answer 1

Try this method

- (NSComparisonResult)caseInsensitiveCompare:(NSString *)aString

Answer 2

A new way to do this. iOS 8

let string: NSString = "Café"
let substring: NSString = "É"

string.localizedCaseInsensitiveContainsString(substring) // true

Answer 3

to check with the prefix as in the iPhone ContactApp

([string rangeOfString:prefixString options:NSCaseInsensitiveSearch].location == 0)

this blog was useful for me

Answer 4

NSMutableArray *arrSearchData;  
NSArray *data=[arrNearByData objectAtIndex:i];
NSString *strValue=[NSString stringWithFormat:@"%@", [data valueForKey:@"restName"]];
NSRange r = [strValue rangeOfString:key options:NSCaseInsensitiveSearch];

if(r.location != NSNotFound)
{
     [arrSearchData addObject:data];
}

Answer 5

You could always ensure they're in the same case before the comparison:

if ([[stringX uppercaseString] isEqualToString:[stringY uppercaseString]]) {
    // They're equal
}

The main benefit being you avoid the potential issue described by matm regarding comparing nil strings. You could either check the string isn't nil before doing one of the compare:options: methods, or you could be lazy (like me) and ignore the added cost of creating a new string for each comparison (which is minimal if you're only doing one or two comparisons).

Answer 6

if( [@"Some String" caseInsensitiveCompare:@"some string"] == NSOrderedSame ) {
  // strings are equal except for possibly case
}

The documentation is located at Search and Comparison Methods