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# addCharacters(in:)

Adds to the receiver the characters whose Unicode values are in a given range.

```
func addCharacters(in aRange: NSRange)
```

## Parameters

`aRange`

The range of characters to add.
`aRange.location` is the value of the first character to add; `aRange.location + aRange.length – 1` is the value of the last. If `aRange.length` is `0`, this method has no effect.

## Discussion

This code excerpt adds to a character set the lowercase English alphabetic characters:

```objc
NSMutableCharacterSet *aCharacterSet = [[NSMutableCharacterSet alloc] init];
NSRange lcEnglishRange;
 
lcEnglishRange.location = (unsigned int)'a';
lcEnglishRange.length = 26;
[aCharacterSet addCharactersInRange:lcEnglishRange];
```

## See Also

  [String Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Strings/introStrings.html#//apple_ref/doc/uid/10000035i)


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