cutting characters off a string
February 17, 2003 05:33 AM
I wish to cut four characters off the end of a string, and replace them with a different four characters, these strings are variable in length and I''m using C++. Is there an easy and efficient way to do this?
122
February 17, 2003 05:45 AM
I think that would depend entirely on how you are storing the strings.
122
February 17, 2003 08:53 AM
Assuming the typical NULL terminated strings in C/C++..
May need slight modification for your exact environment and surrounding code, of course. Incidentally, the while loop is pretty much the same thing strlen() does, but this code does it more directly.
/* CODE FRAGMENT */char * string_to_mangle;int string_index = 0;while( string_to_mangle[string_index++] ) ; /* Do nothing, the work is done in the while test */string_index -= 5; /* subtract 5, to account for the NULL *//* At this point, string_to_mangle[string_index] will point to the 4th char from the end of the string, so you can do what you want to it.. EG: (assume stdio.h, string.h, etc) */strcpy( &string_to_mangle[string_index], "1234" );printf( "%s\n", string_to_mangle );/* Should print the input string, with the last four chars replaced with "1234" */ May need slight modification for your exact environment and surrounding code, of course. Incidentally, the while loop is pretty much the same thing strlen() does, but this code does it more directly.
128
February 18, 2003 05:16 AM
just get the actual strlen(string) and then count backwards replacing the characters in the last 4 fields.
829
February 18, 2003 06:13 AM
szString[ WANTED_LENGTH ] = ''\0'';
[s]--------------------------------------------------------[/s]chromecode.com - software with source code
1,658
February 18, 2003 08:08 AM
C++ strings have a replace member function.
Use it, that''s what it has been designed to do.
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Use it, that''s what it has been designed to do.
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