How do I check if a string contains another string in Objective-C?

Question

How can I check if a string (NSString) contains another smaller string?

I was hoping for something like:

NSString *string = @\"hello bla         


        

Answer 1

An improved version of P i's solution, a category on NSString, that not only will tell, if a string is found within another string, but also takes a range by reference, is:

@interface NSString (Contains)
-(BOOL)containsString: (NSString*)substring
              atRange:(NSRange*)range;

-(BOOL)containsString:(NSString *)substring;
@end

@implementation NSString (Contains)

-(BOOL)containsString:(NSString *)substring
              atRange:(NSRange *)range{

    NSRange r = [self rangeOfString : substring];
    BOOL found = ( r.location != NSNotFound );
    if (range != NULL) *range = r;
    return found;
}

-(BOOL)containsString:(NSString *)substring
{
    return [self containsString:substring
                        atRange:NULL];
}

@end

Use it like:

NSString *string = @"Hello, World!";

//If you only want to ensure a string contains a certain substring
if ([string containsString:@"ello" atRange:NULL]) {
    NSLog(@"YES");
}

// Or simply
if ([string containsString:@"ello"]) {
    NSLog(@"YES");
}

//If you also want to know substring's range
NSRange range;
if ([string containsString:@"ello" atRange:&range]) {
    NSLog(@"%@", NSStringFromRange(range));
}

Answer 2

In Swift 4:

let a = "Hello, how are you?"
a.contains("Hello")   //will return true

Answer 3

NSString *string = @"hello bla bla";
if ([string rangeOfString:@"bla"].location == NSNotFound) {
  NSLog(@"string does not contain bla");
} else {
  NSLog(@"string contains bla!");
}

The key is noticing that rangeOfString: returns an NSRange struct, and the documentation says that it returns the struct {NSNotFound, 0} if the "haystack" does not contain the "needle".

---

And if you're on iOS 8 or OS X Yosemite, you can now do: (*NOTE: This WILL crash your app if this code is called on an iOS7 device).

NSString *string = @"hello bla blah";
if ([string containsString:@"bla"]) {
  NSLog(@"string contains bla!");
} else {
  NSLog(@"string does not contain bla");
}

(This is also how it would work in Swift)

Answer 4

Use the option NSCaseInsensitiveSearch with rangeOfString:options:

NSString *me = @"toBe" ;
NSString *target = @"abcdetobe" ;
NSRange range = [target  rangeOfString: me options: NSCaseInsensitiveSearch];
NSLog(@"found: %@", (range.location != NSNotFound) ? @"Yes" : @"No");
if (range.location != NSNotFound) {
// your code
}

Output result is found:Yes

The options can be "or'ed" together and include:

NSCaseInsensitiveSearch NSLiteralSearch NSBackwardsSearch and more

Answer 5

-(Bool)checkIf:(String)parentString containsSubstring:(String)checkString {
    NSRange textRange =[parentString rangeOfString:checkString];
    return textRange.location != NSNotFound // returns true if parent string contains substring else returns false
  }

Answer 6

NSString *myString = @"hello bla bla";
NSRange rangeValue = [myString rangeOfString:@"hello" options:NSCaseInsensitiveSearch];

if (rangeValue.length > 0)
{
    NSLog(@"string contains hello");
} 
else 
{
    NSLog(@"string does not contain hello!");
}

//You can alternatively use following too :

if (rangeValue.location == NSNotFound) 
{
    NSLog(@"string does not contain hello");
} 
else 
{
    NSLog(@"string contains hello!");
}