nsstring and const char* conversion

Question

i try to convert nsstring to const char*.

1- i add a nsstring and an integer together
2- then i convert this new nsstring to const char*
3- i have an object

Answer 1

const char* are constant, you can't assign them in anyway !

Try passing (const char*)[firstName UTF8String] to your method

Answer 2

Use cStringUsingEncoding from the NSString class:

NSString *myString = @"Hello";
const char *cString = [myString cStringUsingEncoding:NSASCIIStringEncoding];

Answer 3

Use this method:

char* MakeStringCopy (const char* string)
{
    if (string == NULL)
        return NULL;

    char* res = (char*)malloc(strlen(string) + 1);
    strcpy(res, string);
    return res;
}

NSString *filePath = @"~/Documents/Image.png";
MakeStringCopy([filePath UTF8String]);

Answer 4

NSString* firstName = [NSString stringWithFormat: @"Name%d", 1];

const char* secondName = [firstName UTF8String];

UTF8String returns a const char:   - (const char *)UTF8String