How do I convert an integer to string?

There are a few things wrong with your logic:

- The variable size is used by never initialized. I would guess it should be initialized to zero and then incremented in the while loop with the ++ operator.

- Also in the while loop, temp should probably be set with the /= operator.

- Another thing is the str pointer appears to be set using the comparison operator instead of the assignment operator which is a single equals sign.

Here is what your logic looks like with these changes :

void ToString( char* str, int number )
{
    int i;
    int size = 0;
    int temp = number;
    while( temp != 0 )
    {
        temp /= 10;
        ++size;
    }
    for( int i = size - 1; i >= 0; --i )
    {
        *str = ( number / 10 ) + '0';
        str++;
    }

It's still not right but at least the syntax errors have been fixed. I recommend that you run your program in a debugger so you can see what is going on with it. At the very least, add some output statements so you can see the characters as they are added to the string.

You have some errors in your code,

size is not initialized
you have performed an operation on temp but haven't stored it.
Inside the for loop you have used comparsion operator instead of equals'='.

The following code might help in performing the operation

char *itoa(int num) 
{ 
    int i; 
 
    while(num != 0) 
    { 
        str[i++] = num % 10 + '0'; 
        num /= 10; 
    } 
 
    str[i] = '\0'; 
 
   
	return str; 
} 

Greetings May I inquire how is it guaranteed the destination ptr points to sufficient memory to contain all the digits . It does not seem possible to obtain same as the caller would then need to know the conversion already, unless of course it is allocated to contain the maximum possible length of integer converted string to wit i.e. e.g. std::numeric_limits<int>::max() . May I also inquire is this a school assignment? Also the level/year of schooling to wit i.e. Grammar[1-8]? Secondary[1-4]?