How to DELETE one emoji in NSString
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How to Traversal emojis in NSString 
There is a NSString method used to traversal substring of NSString  
    
        NSString *text = @"2012😊我们 😊😊😊😊😊🇺🇸🇷🇺🇰🇷🇯🇵";
        [text enumerateSubstringsInRange:NSMakeRange(0, [text length]) options:NSStringEnumerationByComposedCharacterSequences  usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
        printf("%s- ",[substring UTF8String]);
    }];

Guess what is the output?

The output is :

        2- 0- 1- 2- 😊- 我- 们-  - 😊- 😊- 😊- 😊- 😊- 🇷- 🇺- 🇰- 🇷- 🇯- 🇵-  🇺- 🇸- 

Rather than:

       2- 0- 1- 2- 😊- 我- 们-  - 😊- 😊- 😊- 😊- 😊- 🇷🇺- 🇰🇷- 🇯🇵- 🇺🇸- 

Like the American Flag  🇺🇸 , it's composed by 🇺 and 🇸
The length of a flag seems to be 4, and they are composed by two length-2-composed-character. 
while the NSString is enumerated , it gives me 🇺 and 🇸 rather than 🇺🇸 

When the string is in UITextView, the BACKSPACE in Keyboard is tapped, it can handle to delete   the emoji 🇺🇸 rather than 🇸. 

In my app, I made a custom emoji keyboard and there is a DELETE button. I want to the DELETE button works just like the system BACKSPACE button in keyboard.

Does anyone know how to handle it ?





