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"EL" <lameddie@yahoo.com> wrote...
> How can i compare a char array from defined structure with input char?
> I can't get the expected result from the following coding. Pls help!

Either use strcmp() (for char[]) or switch to using std::string
and use '=='.

Victor
--
Please remove capital A's from my address when replying by mail

On Sat, 26 Jan 2002 01:10:24 +0800, "EL" <lameddie@yahoo.com> wrote:

>Help!
>
>How can i compare a char array from defined structure with input char?
>I can't get the expected result from the following coding. Pls help!
>
>
>struct mystr
>{
>char id[7], name[21];
>};
>
>mystr s[50];
>
>void main()

According to the definitions of the C and C++ languages should main
return an int, so
  int main()
>{
>  int i, j ;
>  char vid[7];
>
<snip>
>   if (vid == s[i].id)

There you are comparing the *addresses* of vid and s[i].id. To compare
the contents of the char arrays, use strcmp():
  if (strcmp(vid, s[i].id) == 0) /* they are equal */

>   {
>   cout << "\nFound id: " << s[i].id;
>   }
>   else
>   {
>   cout << "\nNot found you id " << vid;
>   }
>  }
>}
>
Bart v Ingen Schenau
--
Remove NOSPAM to mail me directly
FAQ for clc: http://www.eskimo.com/~scs/C-faq/top.html
FAQ for acllc-c++: http://snurse-l.org/acllc-c++/faq

Use STL string class
--
Randy Charles Morin
http://www.kbcafe.com

Feel free to contact me by private email or messenger
morin_randy@hotmail.com
randy@kbcafe.com

#include <iostream>

struct mystr
{
char id[7], name[21];
};

mystr s[50];

void main()
{
  int i, j ;
  char vid[7];

  for (i=0; i<2 ; i++)
  {
   std::cout << "Stud ID : ";
   std::cin >> s[i].id;
   std::cout << "Name    : ";
   std::cin >> s[i].name;
  }

  for (i=0; i<2 ; i++)
  {
   std::cout << "ID: " << s[i].id << "\t" << "Name: " << s[i].name << std::endl;
  }

  std::cout << "\nEnter search id: ";
  std::cin >> vid;

  for (i=0; i<2 ; i++)
  {
   if (std::string(vid) == std::string(s[i].id))
   {
   std::cout << "\nFound id: " << s[i].id;
   }
   else
   {
   std::cout << "\nNot found you id " << vid;
   }
  }
}



"EL" <lameddie@yahoo.com> wrote in message news:a2s339$ngo3@imsp212.netvigator.com...
> Help!
>
> How can i compare a char array from defined structure with input char?
> I can't get the expected result from the following coding. Pls help!
>
>
> struct mystr
> {
> char id[7], name[21];
> };
>
> mystr s[50];
>
> void main()
> {
>   int i, j ;
>   char vid[7];
>
>   for (i=0; i<2 ; i++)
>   {
>    cout << "Stud ID : ";
>    cin >> s[i].id;endl;
>    cout << "Name    : ";
>    cin >> s[i].name;endl;
>   }
>
>   for (i=0; i<2 ; i++)
>   {
>    cout << "ID: " << s[i].id << "\t" << "Name: " << s[i].name << endl;
>   }
>
>   cout << "\nEnter search id: ";
>   cin >> vid;endl;
>
>   for (i=0; i<2 ; i++)
>   {
>    if (vid == s[i].id)
>    {
>    cout << "\nFound id: " << s[i].id;
>    }
>    else
>    {
>    cout << "\nNot found you id " << vid;
>    }
>   }
> }
>
>

This code solves the problem (in c++), but probably not in an ideal way.
However there is many different ways to read in the chars:

#include <iostream>
#include <iomanip>

bool StrCmp (char* first, char* second)
{
 for (int i = 0 ; first[i] == second[i] ; i++)
  if (first[i] == 0) return true ;
 return false ;
}

int main ()
{
 char vid[ ] = "MYNAM" ;
 struct mystruct
 {
  char id[7] ;
  /*........*/
 } mys ;

//  7 - 1 chars are transferred, termination
// character is appended onto char array

std::cin.getline (mys.id,7) ;

// Skip leading witespaces, set width to 7, end at white space or 7-1
// characters, append termination charachter

std::cin >> std::ws >> std::setw(7) >> mys.id ;

 if (StrCmp (vid, mys.id))
  std::cout << "Strings equal: "
   << vid << "    " << mys.id
   << std::endl ;
 else
  std::cout << "Strings Do Not Match: "
   << vid << "    " << mys.id
   << std::endl ;
 return 0 ;
}

--
----------------------------------------------------------------------------
----------
Jonas, email: v123@telia.com
----------------------------------------------------------------------------
----------
"EL" <lameddie@yahoo.com> wrote in message
news:a2s339$ngo3@imsp212.netvigator.com...
> Help!
>
> How can i compare a char array from defined structure with input char?
> I can't get the expected result from the following coding. Pls help!
>
>
> struct mystr
> {
> char id[7], name[21];
> };
>
> mystr s[50];
>
> void main()
> {
>   int i, j ;
>   char vid[7];
>
>   for (i=0; i<2 ; i++)
>   {
>    cout << "Stud ID : ";
>    cin >> s[i].id;endl;
>    cout << "Name    : ";
>    cin >> s[i].name;endl;
>   }
>
>   for (i=0; i<2 ; i++)
>   {
>    cout << "ID: " << s[i].id << "\t" << "Name: " << s[i].name << endl;
>   }
>
>   cout << "\nEnter search id: ";
>   cin >> vid;endl;
>
>   for (i=0; i<2 ; i++)
>   {
>    if (vid == s[i].id)
>    {
>    cout << "\nFound id: " << s[i].id;
>    }
>    else
>    {
>    cout << "\nNot found you id " << vid;
>    }
>   }
> }
>
>