IOS/objective-C : Get index of string in array of strings case-insensitive

Question

我正在尝试查找字符串何时匹配(不区分大小写)字符串数组中的字符串，然后获取索引号。当大小写相同时，有一个很好的方法可以做到这一点。或者，下面的代码能够告诉我是否存在不区分大小写的匹配项。但是，当匹配不区分大小写时，我无法让它告诉我索引。

谁能推荐一种方法来做到这一点？

- (NSUInteger)findIndexOfWord:(NSString *)word inString:(NSString *)string {
      NSArray *substrings = [string componentsSeparatedByString:@" "];

     if ([substrings indexOfObjectPassingTest:^(id obj, NSUInteger idx, BOOL *stop){
     return (BOOL)([obj caseInsensitiveCompare:word] == NSOrderedSame);
     }] != NSNotFound) {
     // there's at least one object that matches term case-insensitively
         int index = [substrings indexOfObject:word]; //if a case-insensitive match returns -1.

         return index; // Will be NSNotFound if "word" not found

     }

}

Answer 1

NSString *word = @"YOLO";
NSArray<NSString *> *items = @[ @"hi", @"yolo", @"swag" ];

NSUInteger idx = [items indexOfObjectPassingTest:^BOOL(NSString *obj, NSUInteger idx, BOOL *stop) {
    return [obj caseInsensitiveCompare:word] == NSOrderedSame;
}];

NSLog(@"%lu", (unsigned long)idx);

indexOfObjectPassingTest: Returns the index of the first object in the array that passes a test in a given block.

希望对您有所帮助。请注意，idx 可以是 NSNotFound。