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How to convert NSString to C string?

Asked 2011-07-14T02:25:20.883
47

I know that this question is a possible duplicate, but even after looking at some Google tutorials and questions even on this forum none of them gives me a decent answer about this subject.

I have:

NSString *str = @"text";

And I would like to do something like:

char cstring [512] = str;

(this only shows what I want to do, after looking at Apple's NSString Class Ref I didn't even think about using it).

Up to now I have:

char command [512] = [[NSString stringWithFormat:@"text"] cStringUsingEncoding:NSUTF8StringEncoding];

Still, with that I get errors.

Any solution?

objective-c
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37

A c string is returned as a pointer, not as an array of characters. To use it, you can change your variable to a pointer.

const char *command = [theString cStringUsingEncoding:NSUTF8StringEncoding];

Since you want the UTF8 encoding, you can use the UTF8String convenience method.

const char *command = [theString UTF8String];

If you need the data to be stored in a character array, you can use the getCString:maxLength:encoding: method, passing the array as the buffer. This will allow you to store the string directly to the buffer, and will tell you if the buffer is too small.

char command[512];
if(![theString getCString:command maxLength:sizeof(command)/sizeof(*command) encoding:NSUTF8StringEncoding]) {
    NSLog(@"Command buffer too small");
}
answered 2011-07-14T02:35:19.773

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