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

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");
}

其他回答

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!");
}

在swift的情况下,可以使用这个

let string = "Package #23"
if string.containsString("Package #") {
    //String contains substring
}
else {
    //String does not contain substring
}

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

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

联机(更少的代码。DRY,因为你只有一个NSLog):

NSString *string = @"hello bla bla";
NSLog(@"String %@", ([string rangeOfString:@"bla"].location == NSNotFound) ? @"not found" : @"cotains bla");