How to convert your NSStrings to c strings (const char *) and vice versa in Objective C ?

Objective-C is built upon the C , it’s important to know how to convert C based strings to NSString objects, and vice-versa.
A C string is simply a series of characters (a one-dimensional character array) that is null-terminated, whereas an NSString object is a complete object with class methods, instance methods, etc.​

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1.Coverting C String to Objective C String  (const char * -> NSString)
Answer:
[NSString stringWithCString:string encoding:NSUTF8StringEncoding];

2.Converting Objective C String to C string (NSString => const char *)
Answer:
[string cStringUsingEncoding:NSUTF8StringEncoding];