Creating a string with char[]

Question

#include <iostream>

using namespace std;

int main()
{
    char strin[206];

    strin = "sds";
    cout<<strin;
}

Why do I get this error?

error: incompatible types in assignment of 'const char [4]' to 'char [206]' //on line strin = "sds"

I am following this beginner tutorial

Hehe, Ankur asks "why" and everybody answers "what to do" :) — Roman Saveljev, Apr 09 '13 at 09:02
I recommend ignoring that tutorial. It is... how to put this in nice wor-- nevermind the nice words. It is terrible. You won't learn C++ from it. — R. Martinho Fernandes, Apr 09 '13 at 09:03
@R.MartinhoFernandes +1. I'd just add that for learning C++, SO keeps a list of [good books](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list). — Angew is no longer proud of SO, Apr 09 '13 at 09:11

score 5 · Accepted Answer · answered Apr 09 '13 at 09:01

The error comes from the fact that you're trying to assign one array into another. The assignment operator can't do that; you'd have to copy the array using strcpy() or std::copy().

However, since you want to work in C++, you should really be using std::string instead of char[] to store strings.

masoud · Answer 2 · 2013-04-09T09:07:09.767

2

You can not assign an array to another directly. It should be copied element to element.

Use std::strcpy from <cstring> header

char strin[206];
std::strcpy(strin, "sds");

Use std::string from <string> header

std::string strin;
strin = "sds";

Since you're using C++, choose second one.

edited Apr 09 '13 at 09:07

answered Apr 09 '13 at 09:01

masoud

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score 1 · Answer 3 · answered Apr 09 '13 at 09:01

1

Your code;

strin = "sds";

should be:

strcpy(strin, "sds");

answered Apr 09 '13 at 09:01

Mats Petersson

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score 0 · Answer 4 · answered Apr 09 '13 at 09:03

C/C++ doesn't have string opertions built-in. You need to use either function:

strcpy(strin, "sds"); // will work in C and C++
// strncpy(strin, "sds", 205); // safer if you want to copy user-given string

or std::string:

std::string strin(206, 0);

strin = "sds"; // only C++

score 0 · Answer 5 · answered Apr 09 '13 at 09:04

0

strin is a array which is a const pointer to chars, not a pointer to chars. You tried to change the const pointer and this is forbidden

you need to copy the string. e.g. this way

strcpy (string, "sds");

(Aware buffer overflows in general cases!)

answered Apr 09 '13 at 09:04

stefan bachert

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So what i understood is that when copying an array, you do not actually clone the array but just get a reference to the original array, is that right? – Joe Slater Apr 09 '13 at 09:16
`xys = "123"` does not copy, it just changes the pointer (if allowed). In this way it is right – stefan bachert Apr 09 '13 at 09:19

Creating a string with char[]

5 Answers5