String Manipulation

[SteveCRM]

Okay now I have my text from a file. Is there an easy way to search the string other than making some huge function?

[jim mcnamara]

in C

strchr(bigstring, character) looks for a char in a string
str(bigstring, littlestring) looks for a small string in a big one

C++

CString has instr to find substrings.

[SteveCRM]

what header is needed?

error C2065: 'str' : undeclared identifier

[parksie]

CString is MFC, Jim For normal C++ it's best to use string.

However, if it's a large file (more than about 250K), it can be a lot faster to use a rope.

[jim mcnamara]

oops -

strstr(bigstring, littlestring);

my typo.

If you go into VC++ help and look up strcmp( ) or any other string thing - you have a link to all of the functions as well as CString.

Parskie is right - but th eonly serious code I've written in C++ was MFC - a while back. I'm back to C at work now.

[CornedBee]

parksie: what is a rope? I never heard of it.

[kedaman]

I haven't used the STL::rope yet but it's suppose be a string that is good for frequent concentrations of long strings, in contrast to char arrays which would take linear time to concentrate.
http://www.sgi.com/tech/stl/Rope.html

[SteveCRM]

okay this strstr() function is really throwing me off. How do I use it? I just want to know where the little string is in the big string (like vb's InStr).

[jim mcnamara]

#include <stdio.h>

void main(void){
  char *buf, *s;
  int where;
  char bigstring[100];
  char littlestring[10];

  memset(littlestring,'\0',sizeof(littlestring) );/* zero out memory */
  memset(bigstring,'\0',sizeof(bigstring) );
  strcpy(bigstring,"this is a test.");  /* put stuff in test strings */
  strcpy(littlestring,"is");

  buf = (char*) strstr(bigstring,littlestring); /* do instr( ) */
  if (buf != NULL) {/* we found one if buf != NULL */
     s = bigstring;
     where = buf - s;
     printf("position = %d\n",where);
  }
  else {
       printf("Not found. \n");
  }
}