How to search a subString from a NSString with case-insensitive

I knew a instance method of NSString.

- (NSRange)rangeOfString:(NSString *)aString

My source string looks like this: "abcdEFGhi"

When I use [srcStr.rangeOfString:@"efg"];, there开发者_StackOverflow is no substring was found.

How can I solve this problem?

There is one more version of rangeOfString method you could use that.

- (NSRange)rangeOfString:(NSString *)aString options:(NSStringCompareOptions)mask

So use as below

[srcStr rangeOfString:@"efg" options:NSCaseInsensitiveSearch];

I think you're looking for:

[srcStr rangeOfString:@"efg" options:NSCaseInsensitiveSearch];