asked on

Finding an InString Method for C

Hi,

I need an inString function that returns a 0 or 1 to use in my IF statements. I do not think the attached code is correct, and I would love it if I could tap someone's brain to get a working solution.

I searched on here already and could not find anything.

I would like to make this so that I can search for any sized string in the first string.

Thanks

static int inString(const char* testvalue, char token[1])
{
	// variables
	int i;
	// resolve token in string
	for (i = 0; i < strlen(testvalue); i++)
		if (testvalue[i] == token)
			return 1;
	// return
	return 0;
}

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phoffric

I think you probably are looking for one of these two library functions:
http://www.cplusplus.com/reference/clibrary/cstring/strchr/

http://www.cplusplus.com/reference/clibrary/cstring/strstr/

dilithiumtoys_dot_com

ASKER

Neither function seems to be working for me. Specifically I need to find if a character exists in the string and get a Boolean/testable value from it. How do I test either to determine if the character is actually in the string?

Subrat (C++ windows/Linux)

strchr() can do your job. I don't know how it's not working for you.

Have a look on the below code

#include "stdio.h"
#include "string.h"

int inString(const char* testvalue, char token) {
const char* retval = strchr(testvalue, token);
if(retval == NULL)
return 0;
else
return 1;
}

int main() {
int res = inString("Subrat", 's');
printf(res?"Charecter present\n":"Char not present\n");
res = inString("Subrat",'S');
printf(res?"Charecter present\n":"Charecter not present\n");
return 0;
}

phoffric

>> Neither function seems to be working for me. Specifically I need to find if a character exists in the string and get a Boolean/testable value from it.

If you post the code that does not work for you, then we can help fix it. As this problem is a typical academic assignment, I was unable to provide you with code. But, if you want to learn how to find the problem yourself, just post your code for our advice.

phoffric

Did you copy the code in the strchr link and try to make it fit for your program? Here is the sample code:

/* strchr example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char str[] = "This is a sample string";
  char * pch;
  printf ("Looking for the 's' character in \"%s\"...\n",str);
  pch=strchr(str,'s');
  while (pch!=NULL)
  {
    printf ("found at %d\n",pch-str+1);
    pch=strchr(pch+1,'s');
  }
  return 0;
}

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dilithiumtoys_dot_com

ASKER

Hi,

I am using SubRat2009's example in the attached code, but with strstr(). I am passing in

str1 = "eula.txt"
str2 = "."

I am getting the integer 0 as a result, when I should be getting 1 back. Whats wrong?

Thanks

static int inString(const char* str1, const char* str2)
{
	// variables
	const char* retval; 
	// check string length
	if (strlen(str1) == 0 || strlen(str2) == 0)	
		return 0;
	// resolve string
	retval = strstr(str1, str2);
	// return the result
	if(retval == NULL)
		return 0;
	else
		return 1;
}

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ASKER CERTIFIED SOLUTION

Subrat (C++ windows/Linux)

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