is there something wrong with this input user code? [closed] - c++

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#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <iostream>
using namespace std;
struct customer
{
char fname[11];
};
void name(customer& name)
{
bool check = false;
do {
cout << "Enter your first name : ";
cin.getline(name.fname, 10);// goal is to exit once press enter
if (name.fname == '\n') //This doesnt work. i also tried using cin.get, cin.ignore, cin.peek and it still doesnt work, i tried changing the '\n' to '\0' and 0 just to see.
{
cout << "Invalid Entry\n";
}
else
check = true;
} while (check != true);
}
int main()
{
customer cr;
name(cr);
return 0;
}
I created this code just to finally figure out how to use cin.getline(), its a simple code where it takes a name.
The goal is to enter a name and exit the code when pressing Enter.

Answer 1

you dont mean
if (name.fname == '\n')
you mean
if (name.fname[0] == '\n')

Answer 2

You are trying to compare a char[] array to a single char, which will not work. Use a string comparison like strcmp() instead. However, cin.getline() will not store the terminating '\n' into fname to begin with.
Try something more like this instead:
#define _CRT_SECURE_NO_WARNINGS
#include <cstring>
#include <iostream>
using namespace std;
struct customer
{
char fname[11];
};
void name(customer& name)
{
bool check = false;
do {
cout << "Enter your first name : ";
if (!cin.getline(name.fname, 11))
break;
//if (name.fname[0] == '\0')
if (strcmp(name.fname, "") == 0)
cout << "Invalid Entry\n";
else
check = true;
}
while (!check);
}
int main()
{
customer cr;
name(cr);
return 0;
}
That said, you really should be using std::string instead of char[], eg:
#define _CRT_SECURE_NO_WARNINGS
#include <string>
#include <iostream>
using namespace std;
struct customer
{
string fname;
};
void name(customer& name)
{
bool check = false;
do {
cout << "Enter your first name : ";
if (!getline(cin, name.fname))
break;
if (name.fname == "")
cout << "Invalid Entry\n";
else
check = true;
}
while (!check);
}
int main()
{
customer cr;
name(cr);
return 0;
}

Answer 3

Try this code
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstring>
struct customer
{
char fname[11];
};
void name(customer& name)
{
bool check = false;
do {
std::cout << "Enter your first name : ";
std::cin.getline(name.fname, 10);
if (std::cin.fail() || name.fname[0] == '\n')
{
std::cout << "Invalid Entry\n";
std::cin.clear();
std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
}
else
check = true;
} while (check != true);
}
int main()
{
customer cr;
name(cr);
return 0;
}