---
title: "CFStringInsert(_:_:_:)"
framework: corefoundation
role: symbol
role_heading: Function
path: "corefoundation/cfstringinsert(_:_:_:)"
---

# CFStringInsert(_:_:_:)

Inserts a string at a specified location in the character buffer of a CFMutableString object.

## Declaration

```swift
func CFStringInsert(_ str: CFMutableString!, _ idx: CFIndex, _ insertedStr: CFString!)
```

## Parameters

- `str`: The string to be modified. If this value is not a CFMutableString object, an assertion is raised.
- `idx`: The index of the character in str after which the new characters are to be inserted. If the index is out of bounds, an assertion is raised.
- `insertedStr`: The string to insert into str.

## Discussion

Discussion To accommodate the new characters, this function moves any existing characters to the right of the inserted characters the appropriate number of positions.

## See Also

### CFMutableString Miscellaneous Functions

- [CFStringAppend(_:_:)](corefoundation/cfstringappend(_:_:).md)
- [CFStringAppendCharacters(_:_:_:)](corefoundation/cfstringappendcharacters(_:_:_:).md)
- [CFStringAppendCString(_:_:_:)](corefoundation/cfstringappendcstring(_:_:_:).md)
- [CFStringAppendFormatAndArguments(_:_:_:_:)](corefoundation/cfstringappendformatandarguments(_:_:_:_:).md)
- [CFStringAppendPascalString(_:_:_:)](corefoundation/cfstringappendpascalstring(_:_:_:).md)
- [CFStringCapitalize(_:_:)](corefoundation/cfstringcapitalize(_:_:).md)
- [CFStringCreateMutable(_:_:)](corefoundation/cfstringcreatemutable(_:_:).md)
- [CFStringCreateMutableCopy(_:_:_:)](corefoundation/cfstringcreatemutablecopy(_:_:_:).md)
- [CFStringCreateMutableWithExternalCharactersNoCopy(_:_:_:_:_:)](corefoundation/cfstringcreatemutablewithexternalcharactersnocopy(_:_:_:_:_:).md)
- [CFStringDelete(_:_:)](corefoundation/cfstringdelete(_:_:).md)
- [CFStringFindAndReplace(_:_:_:_:_:)](corefoundation/cfstringfindandreplace(_:_:_:_:_:).md)
- [CFStringFold(_:_:_:)](corefoundation/cfstringfold(_:_:_:).md)
- [CFStringLowercase(_:_:)](corefoundation/cfstringlowercase(_:_:).md)
- [CFStringNormalize(_:_:)](corefoundation/cfstringnormalize(_:_:).md)
- [CFStringPad(_:_:_:_:)](corefoundation/cfstringpad(_:_:_:_:).md)