我如何检查一个字符串(NSString)包含另一个较小的字符串?

我希望是这样的:

NSString *string = @"hello bla bla";
NSLog(@"%d",[string containsSubstring:@"hello"]);

但我能找到的最接近的是:

if ([string rangeOfString:@"hello"] == 0) {
    NSLog(@"sub string doesnt exist");
} 
else {
    NSLog(@"exists");
}

不管怎样,这是找出字符串是否包含另一个字符串的最好方法吗?


当前回答

使用选项nsscaseinsensitivesearch与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
}

输出结果:Yes

选项可以用“或”加在一起,包括:

NSCaseInsensitiveSearch NSLiteralSearch NSBackwardsSearch等等

其他回答

因为这似乎是谷歌中的一个高级结果,我想添加这个:

iOS 8和OS X 10.10在NSString中添加了containsString:方法。Dave DeLong关于这些系统的例子的更新版本:

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

对于iOS 8.0+和macOS 10.10+,你可以使用NSString的本地containsString:。

对于旧版本的iOS和macOS,你可以为NSString创建自己的(过时的)类别:

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

// - - - - 

@implementation NSString ( SubstringSearch )

- (BOOL)containsString:(NSString *)substring
{    
    NSRange range = [self rangeOfString : substring];
    BOOL found = ( range.location != NSNotFound );
    return found;
}

@end

注意:观察Daniel Galasko下面关于命名的评论

在Swift 4中:

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

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");
}