第一串是否包含第二串，

NSString *first = @"Banana";
NSString *second = @"BananaMilk";
NSRange range = [first rangeOfString:second options:NSCaseInsensitiveSearch];

if (range.length > 0) {
    NSLog(@"Detected");
}
else {
    NSLog(@"Not detected");
}

如果你需要这样做，可以这样写:

NSString *stringToSearchThrough = @"-rangeOfString method finds and returns the range of the first occurrence of a given string within the receiver.";
BOOL contains = [stringToSearchThrough rangeOfString:@"occurence of a given string"].location != NSNotFound;

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!");
}

//你也可以使用下面的语句:

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

试试这个:

Swift 4.1、4.2:

let stringData = "Black board"

//swift quick way and case sensitive
if stringData.contains("bla") {
    print("data contains string");
}

//case sensitive
if stringData.range(of: "bla",options: .caseInsensitive) != nil {
    print("data contains string");
}else {
    print("data does not contains string");
}

objective - c:

NSString *stringData = @"Black board";

//Quick way and case sensitive
if ([stringData containsString:@"bla"]) {
    NSLog(@"data contains string");
}

//Case Insensitive
if ([stringData rangeOfString:@"bla" options:NSCaseInsensitiveSearch].location != NSNotFound) {
   NSLog(@"data contains string");
}else {
   NSLog(@"data does not contain string");
}

如果不介意区分大小写的字符串。 试试这个。

NSString *string  = @"Hello World!";

if([string rangeOfString:@"hello" options:NSCaseInsensitiveSearch].location !=NSNotFound)
{
    NSLog(@"found");
}
else
{
    NSLog(@"not found");
}

所以我个人非常讨厌NSNotFound，但是理解它的必要性。

但是有些人可能不理解与NSNotFound比较的复杂性

例如，下面的代码:

- (BOOL)doesString:(NSString*)string containString:(NSString*)otherString {
    if([string rangeOfString:otherString].location != NSNotFound)
        return YES;
    else
        return NO;
}

有它的问题:

1)显然，如果otherString = nil这段代码将崩溃。一个简单的测试是:

NSLog(@"does string contain string - %@", [self doesString:@"hey" containString:nil] ? @"YES": @"NO");

结果!!崩溃! !

2)对于objective-c的新手来说，不太明显的是，当string = nil时，相同的代码不会崩溃。 例如，下面的代码:

NSLog(@"does string contain string - %@", [self doesString:nil containString:@"hey"] ? @"YES": @"NO");

这段代码:

NSLog(@"does string contain string - %@", [self doesString:nil containString:nil] ? @"YES": @"NO");

都会导致

does string contains string - YES

这显然不是你想要的。

所以我认为更好的解决方案是使用rangeOfString返回0的长度，然后一个更好更可靠的代码是这样的:

- (BOOL)doesString:(NSString*)string containString:(NSString*)otherString {
    if(otherString && [string rangeOfString:otherString].length)
        return YES;
    else
        return NO;
}

或者仅仅是:

- (BOOL)doesString:(NSString*)string containString:(NSString*)otherString {
    return (otherString && [string rangeOfString:otherString].length);
}

对于情况1和2哪种会返回

does string contains string - NO

这是我的2美分;-)

请查看我的Gist以获得更多有用的代码。