Comparing the values of char arrays in C++

Question

I have problem about doing something in my program. I have a char[28] array keeping names of people. I have another char[28] array that also keeps names. I ask user to enter

Answer 1

You can write code for your own char array compare function. Let's start

//Return 0 if not same other wise 1
int compare(char a[],char b[]){
    for(int i=0;a[i]!='\0';i++){
        if(a[i]!=b[i])
            return 0;
    }
    return 1;
}

Answer 2

if( sName == Student.name ) is comparing the addresses

if( strcmp( sName, Student.name ) == 0 { 
  / * the strings are the same */
}

Be careful with strcmp though

Answer 3

Assuming student::name is a char array or a pointer to char, the following expression

sName==Student.name

compares pointers to char, after decaying sName from char[28] to char*.

Given that you want to compare the strings container in these arrays, a simple option is to read the names into std::string and use bool operator==:

#include <string> // for std::string

std::string sName;
....

if (sName==Student.name)//Student.name is also an std::string

This will work for names of any length, and saves you the trouble of dealing with arrays.

Answer 4

You can compare char arrays that are supposed to be strings by using the c style strcmp function.

if( strcmp(sName,Student.name) == 0 ) // strings are equal

In C++ you normally don't work with arrays directly. Use the std::string class instead of character arrays and your comparison with == will work as expected.

Answer 5

The problem is in if(sName==Student.name) which basically compares the address of the arrays, not their values.
Replace it with (strcmp(sName, Student.name) == 0)

But in general, you are working on C++, not C, I would advise working with std::string which will make this much simpler.