last-character-in-a-string.md

description

Learn more about: Last Character in a String

title

Last Character in a String

ms.date

11/04/2016

helpviewer_keywords

last character in string

MBCS [C++], last character in string

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0a180376-4e55-41e8-9c64-539c7b6d8047

ms.topic

how-to

Last Character in a String

Use the following tips:

Trail byte ranges overlap the ASCII character set in many cases. You can safely use bytewise scans for any control characters (less than 32).
Consider the following line of code, which might be checking to see if the last character in a string is a backslash character:
```
if ( sz[ strlen( sz ) - 1 ] == '\\' )    // Is last character a '\'?
    // . . .
```
Because strlen is not MBCS-aware, it returns the number of bytes, not the number of characters, in a multibyte string. Also, note that in some code pages (932, for example), '\' (0x5c) is a valid trail byte (sz is a C string).

One possible solution is to rewrite the code this way:
```
char *pLast;
pLast = _mbsrchr( sz, '\\' );    // find last occurrence of '\' in sz
if ( pLast && ( *_mbsinc( pLast ) == '\0' ) )
    // . . .
```
This code uses the MBCS functions _mbsrchr and _mbsinc. Because these functions are MBCS-aware, they can distinguish between a '\' character and a trail byte '\'. The code performs some action if the last character in the string is a null ('\0').